12V DC Wire Gauge Calculator
Size 12V or 24V accessory wire by voltage drop: amp draw, one-way feet, and a 3% default. Minimum AWG, actual drop, and…
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Add any TestTalkHQ calculator to your blog, shop site, or training portal. Free forever — no signup, no API key, mobile-responsive, and always up to date.
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2D Sheet Nesting Optimizer Calculator
Nest rectangles, circles, and DXF/concave parts on sheet metal and plate. True-shape nesting into negative space, kerf gaps, multi-sheet overflow, and…
Acv Vs Replacement Cost Calculator
Free online Acv Vs Replacement Cost Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Advanced Voltage Drop Calculator
Free advanced voltage drop calculator with NEC compliance check. Enter wire gauge, length, and load to get drop percentage and recommendations.
Air Compressor Altitude Derate Calculator
Work out how much SCFM an air compressor really delivers at elevation. Barometric pressure from site altitude, humidity-corrected derate, capacity lost, the…
Air Compressor CFM Calculator
Calculate exactly how much CFM your air compressor needs for any tool combination. Enter your tools and get instant results with tank…
Air Compressor Horsepower Calculator
Work out the horsepower an air compressor genuinely needs and whether yours earns its power bill. Enter capacity in acfm, full-load operating…
Air Compressor Room Ventilation Calculator
Size the exhaust fan and intake louver for an air compressor room. Converts motor horsepower or measured package kW into the heat…
Air Compressor Runtime Calculator
Free air compressor runtime calculator. Enter tank size, PSI range, and CFM draw to estimate how long your tank will last per…
Air Compressor Tank Size Calculator
Free air compressor tank size calculator. Enter your CFM demand and duty cycle to find the minimum tank size for your tools…
Angle Grinder Disc Speed Calculator
Free disc-speed calculator. Enter diameter and RPM — verify you are under the disc max so the wheel does not burst. Instant…
Arc Flash Boundary Calculator
Free arc flash boundary and incident energy calculator. Estimate cal/cm², arc flash boundary distance, and NFPA 70E PPE category from voltage, fault…
Attic Ventilation Calculator
Calculate attic net free ventilation area from IRC R806.2: 1:150 default, 1:300 with the exception, split into intake and exhaust NFA in…
Bandsaw Blade Selection & Speed Calculator
Free bandsaw blade calculator. Pick TPI and blade speed (SFM) by material, stock size, and blade type — bi-metal, carbide, or carbon.…
Bend Allowance / Flat-Pattern Unfolder Calculator
Chain multiple press-brake bends into a complete flat blank. Outside/mold-line or inside/flat-leg mode, printable PDF with reference square, DXF, CSV, and…
Board Foot Calculator
Calculate board feet per piece and total board feet from nominal thickness, width, length, and quantity. Optional $/board-foot estimated cost.
Bolt-Circle / Hole-Pattern Generator Calculator
Calculate X/Y coordinates for bolt circles, grids, and linear hole patterns. Full-scale printable PDF drilling template, G-code starting point, and CSV export.
Bolt Torque Calculator
Free bolt-torque calculator. Enter size, grade, and lube — get ft-lb for steel fasteners. Instant tightening numbers, no signup. Use it free…
Boring Bar Speed and Feed Calculator
Calculate boring bar RPM, feed rate, and depth of cut for any material. Includes L/D chatter risk warning for HSS and carbide…
Box Fill Calculator
Free electrical box fill calculator per NEC Article 314. Enter conductors, devices, and clamps to check box fill and avoid code violations.…
Braking / Stopping Distance Calculator
Estimate reaction, braking, and total stopping distance from speed, reaction time, and road surface. Physics estimate under assumed conditions — not a…
BTU / Tonnage Cooling Load Calculator
Estimate residential cooling tons and BTU/hr from square footage, climate, ceiling height, and insulation. Starting point only — not ACCA Manual J.
Bundling Discount Estimator
Free online Bundling Discount Estimator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Business Interruption Estimator
Free online Business Interruption Estimator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Cable Tray Fill Calculator
Free NEC 392.22 cable tray fill calculator. Enter tray type, width, cable outside diameters and quantities — get multiconductor and single-conductor fill…
Cargo Securement Tiedown Calculator
Work out how many tiedowns a load actually needs. Enter the weight and length of the article, whether it is blocked against…
CFM Calculator
Free CFM calculator for sizing air compressors. Enter your tools and usage and get the airflow you need to keep your compressor…
Per-Tool Compressed Air (CFM) Requirement Calculator
Look up typical CFM @ 90 PSI for impacts, HVLP, sanders, plasma, sandblasters, and more — with duty-cycle sizing guidance for continuous…
Chip Load Calculator
Free chip load calculator — solve feed rate from IPT or back-calculate chip load from programmed feed. Reference table for aluminum, steel,…
Circuit Breaker Sizing Calculator
Free circuit breaker sizing calculator for electricians. Enter load amperage and get the correct breaker size per NEC overcurrent protection rules.
CNC Plasma Pierce Height & Cut Speed Calculator
CNC plasma starting points: pierce height, pierce delay, cut height, and cut speed (IPM) from material, thickness, and 40–105A process amps. Dial-in…
Coinsurance Penalty Calculator
Free online Coinsurance Penalty Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Combustion Air Opening Calculator
Size combustion air openings for gas appliances to IFGC Section 304 and IRC Section G2407. Enter the total input of every appliance…
Commercial Load Calculator
Free NEC 220 Part III calculator. Enter occupancy and sq ft — get lighting VA, demand, and service amps for retail, office,…
Compressed Air Condensate Calculator
Work out how many gallons of water an air compressor produces each day. Inlet moisture load from temperature and humidity, condensate dropped…
Compressed Air Cost Calculator
Free compressed air cost calculator. Enter compressor HP, tank size, and hours to estimate electricity cost and cost per CFM of compressed…
Compressed Air Leak Calculator
Measure how much air your shop is leaking and what it costs. Run a pressure-decay test, a load/unload duty-cycle test, or estimate…
Compressed Air Pipe Size Calculator
Size shop compressed air pipe by real pressure drop. Darcy-Weisbach with Crane TP-410 fitting equivalents, Schedule 40 steel and Type L copper…
Concrete Volume Calculator
Free concrete volume calculator for slabs, footings, and columns. Enter dimensions and get cubic yards and bags needed instantly. Use it free…
Conduit Bending Calculator
Calculate conduit bending measurements for stub-ups, offsets, 3-point saddles, and box offsets. EMT deduct table included. Free, no signup. Use it free…
Conduit Bending Layout Generator Calculator
Compute mark positions for offset, 3-point saddle, rolling offset, and segmented 90° conduit bends. Big on-screen numbers for phone use at the…
Conduit Fill Calculator
Free NEC conduit-fill calculator. Enter conduit type, trade size, and wire counts — get fill percent before you pull. Instant pass/fail. Use…
Cone / Transition Flat-Pattern Template Generator Calculator
Generate full-scale printable flat patterns for full cones, frustum transitions, and lobster-back elbows. Tiled PDF with reference square — add your own…
Coolant Mix Ratio Calculator
Coolant mix ratio calculator for ethylene glycol antifreeze. Quarts or liters of concentrate and distilled water for a target freeze/boil point at…
Countersink & Counterbore Depth Calculator
Calculate countersink depth, counterbore depth, and pilot hole diameter instantly. Enter screw size and angle — get the exact dimensions you need.
Cut-Cost & Time Estimator Calculator
Estimate laser, plasma, or waterjet cut time and cost from manual cut length or a client-side DXF upload. Export a one-page PDF…
Cut List Optimizer Calculator
Optimize 1D cut lists for metal bar, tube, and lumber. Enter standard stock and remnants, account for kerf, and export a printable…
Cutting Speed & Feed Rate Calculator
Free CNC calculator. Enter SFM, cutter diameter, and flutes — get RPM, chip load, and IPM for mill, drill, and tap. Instant…
Deck Beam Span Calculator
Look up maximum deck beam span from IRC 2021 Table R507.5(1) by species, plies, size, and effective joist span. Starting point only…
Deck Footing Size Calculator
Look up minimum deck footing size from IRC 2021 Table R507.3.1 by live/snow load, tributary area, and soil bearing. Starting point only…
Deck Ledger Board Fastener Calculator
Calculate 1/2-inch lag screw or through-bolt on-center spacing for a deck ledger from joist span, plus fastener count for the ledger length.…
Deck Post Spacing Calculator
Look up maximum deck post spacing from IRC 2021 Table R507.5(1) by beam size, species, and joist span. Starting point only —…
Deck Stair Calculator
Calculate exterior deck stair layout: step count, rise and run per step, treated 2x12 stringer length, 2 or 3 stringers, and a…
Delta-T (Temperature Split) Calculator
Calculate HVAC delta-T from return and supply air temperature. Expected cooling split ~16–22°F, adjusted for outdoor humidity and temperature, with…
Drain Pipe Slope Calculator
Minimum drain-pipe drop from IPC Table 704.1 by diameter and run length. Inches per foot, percent, and a joist-bay check. Prescriptive starting…
Drill Speed Calculator
Free drill speed and feed rate calculator. Get recommended RPM and feed by drill bit size, material, and operation for accurate, clean…
Drip Edge Calculator
Drip edge calculator: eave + rake linear feet and 10-ft stock pieces with 3 in IRC R905.2.8.5 joint overlap. Planning only —…
Duct CFM Calculator
Calculate duct CFM from an anemometer traverse (FPM) and round or rectangular inside area. Average multiple points — not a single center-point…
HVAC Duct Sizing Calculator (Ductulator)
Size round or rectangular sheet-metal duct from CFM and friction rate with the equal-friction method. Velocity check, PDF result card, reference table,…
Ductless Mini-Split Sizing Calculator
Size ductless mini-split BTU per room and total system load from zone sq ft, climate, insulation, sun, and occupants. Multi-zone head count…
Duty Cycle Calculator – Calculate Weld Time & Cool Down Period
Free duty cycle calculator for welders. Enter your welder's duty cycle rating and amperage to get safe weld time and required cool-down…
DWV Vent Sizing Calculator
Minimum individual/branch vent from IPC 2021 §906.2 by DFU and developed length, plus UPC Table 703.2. Prescriptive starting point — not a…
DXF Viewer, Measure & Cleanup
Free online DXF viewer: pan, zoom, measure distance and angle, toggle layers, delete stray lines, auto-clean duplicates, and export a clean DXF…
Electrode & Wire Consumption Calculator
Use our electrode wire consumption calculator to estimate welding wire usage by weld size, length, process, and material. Use it free on…
Engine Compression Ratio Calculator
Work out static compression ratio from bore, stroke, combustion chamber volume, head gasket bore and compressed thickness, piston dish or dome volume…
Equipment Grounding Conductor Calculator
Size the equipment grounding conductor (EGC) per NEC Table 250.122 from overcurrent device rating. Copper or aluminum — not service conductor size…
EV Charger Circuit Sizing Calculator
Free EV charger circuit sizing calculator. Enter charger output and get wire gauge, breaker size, and conduit fill for your installation. Use…
Expansion Tank Sizing Calculator
Size a thermal expansion tank from water-heater gallons, incoming pressure, PRV setting, and temperature rise. Boyle’s-law acceptance volume. Starting…
Extension Cord Voltage Drop Calculator
Calculate extension cord voltage drop and recommended AWG gauge for tools, welders, and jobsite runs. Distinct from the voltage-drop-calculator (branch…
External Static Pressure (ESP) Calculator
Calculate total external static pressure from supply and return duct readings and compare it to the blower’s rated ESP — over/under status…
Fall Clearance Calculator
Free fall clearance calculator for fall arrest. Required clearance from free fall, deceleration, harness stretch, and safety factor vs available clearance.…
Feeder / Service Load Calculator
Free feeder and service load calculator for electricians. Calculate total demand load for service entrance and feeder conductor sizing. Use it free…
Fence Post Spacing & Concrete Calculator
Fence-line post count, actual on-center spacing, and bagged concrete from fence type, height, run, hole size, and frost climate. Not IRC deck…
Filler Metal Weight Calculator
Free filler-metal weight calculator. Enter material, diameter, length, and quantity — get rod and wire pounds instantly. No signup required.
Fillet Weld Strength Calculator
Free fillet weld strength calculator per AWS D1.1 and AISC. Get weld load capacity, throat size, and pass/fail check for structural welds.…
Fixture Unit Calculator
Total WSFU from IPC 2021 Table E103.3(2) and DFU from Table 709.1. Then size supply, vent, and drain. Prescriptive starting point —…
Flux Core Welding Calculator
Free flux-core welding calculator. Get wire feed speed, voltage, and amperage recommendations by material type and thickness. Field-ready. Use it free on…
Furnace Sizing Calculator
Estimate furnace heating BTU output from square footage, climate zone, insulation, and ceiling height, then convert to furnace input rating by AFUE.…
Gas Cylinder Duration Calculator
Calculate how long your argon, CO2, or mixed shielding gas cylinder will last based on tank size (cu ft), flow rate (CFH),…
Gas Pipe Sizing Calculator
Size natural gas or propane Schedule 40 steel and CSST from IFGC Table 402.4 capacity tables by BTU load, developed length, and…
Gear Ratio & RPM Calculator
Calculate engine RPM at a road speed, or road speed at a target RPM, from tire diameter, axle ratio, and transmission gear.…
Generator Fuel Consumption & Runtime Calculator
Estimate generator fuel burn and how long your tank will last at a given load. Complements generator-sizing-calculator (capacity) with runtime/fuel focus…
Generator Sizing Calculator
Free generator sizing calculator. Enter your loads and get the minimum generator wattage you need for home, shop, or jobsite use. Use…
Generator Transfer Switch Calculator
Free generator transfer switch sizing calculator. Enter your generator wattage and get the right amp rating, circuit count, and switch type for…
Groove / Butt Weld Strength Calculator
Calculate groove and butt weld strength per AWS D1.1 / AISC — CJP and PJP effective throat, design strength, and capacity check.…
Grounding Electrode Conductor Sizing Calculator
Size the grounding electrode conductor (GEC) per NEC Table 250.66 from your largest ungrounded service conductor. Copper or aluminum, with 250.66(A)–(C)…
Grouped Motor Circuit Sizing Calculator
Size multiple motors on one circuit: NEC 430.24 feeder ampacity and 430.53 group protection. Enter each motor HP and voltage — get…
Guardrail Baluster Spacing Calculator
Calculate baluster count, clear gap, and on-center spacing for a rail opening so a 4" sphere cannot pass (IRC R312.1.3). Starting point…
Gutter & Downspout Sizing Calculator
Size gutters and downspouts from roof plan area, pitch, and rainfall intensity using IPC Equation 11-1 and Table 1106.6. 5" vs 6"…
Header Size Calculator
Calculate door/window header size from IRC tables: opening width, species/grade, jack studs, snow or building width, and bearing vs partition.
Heat Input Calculator
Free AWS heat-input calculator. Enter amps, volts, and travel speed — get kJ/in for procedure compliance. Instant result, no signup. Use it…
Heat Pump Balance Point Calculator
Find the outdoor temperature at which a heat pump can no longer carry the house, and how much backup heat has to…
Hip / Valley Rafter Length Calculator
Calculate hip and valley rafter length from common-rafter run and roof pitch. Diagonal run = run × 1.4142, then length, plumb cut,…
Horsepower & Torque Calculator
Calculate horsepower from torque and RPM, or torque from horsepower and RPM. Uses the published 5252 constant. Crosses at 5,252 RPM on…
Hot Work & Fire Watch Permit Checklist
Printable hot work permit checklist covering the 35-foot rule, fire watch during and after work, combustible clearance, and post-work sign-off for welding…
HVAC Job Cost & Pricing Calculator
Price an HVAC service call, repair, or change-out: labor hours, equipment, refrigerant, ductwork, disposal, permit, overhead, and markup or margin into a…
Ice & Water Shield Coverage Calculator
Calculate ice and water shield coverage from IRC R905.1.2: 24 in inside the exterior wall line, converted along the roof slope, plus…
Interpass Temperature Calculator
Calculate maximum interpass temperature for welding steel, stainless, and aluminum by material and process. Prevent heat damage and maintain weld quality.
Deck & Floor Joist Span Calculator
Look up maximum joist span from IRC 2021 tables by species, size, spacing, and floor vs deck. Starting point only — verify…
Knurling Calculator
Calculate the correct starting diameter for knurling. Enter target diameter and knurl pitch to get teeth count, starting OD, RPM, and infeed…
kW to kVA to Amps Calculator
Convert between kilowatts (kW), kilovolt-amperes (kVA), and amps for single-phase and three-phase power. Free electrical converter for generators, motors,…
Lathe Turning Speed and Feed Calculator
Calculate lathe turning RPM, feed rate, depth of cut, and material removal rate for any material and tool. SFM-based turning speeds for…
Load Calculation Calculator
Free NEC 220.82 dwelling calculator. Enter sq ft, appliances, and HVAC — get optional-method demand amps for a house panel. Not commercial…
Loan Amortization Calculator
Free online Loan Amortization Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Lockout/Tagout (LOTO) Safety Checklist
Interactive OSHA-based lockout/tagout checklist: notify, shut down, isolate, lock/tag, relieve stored energy, verify zero energy — with per-energy-source…
Markup Vs Margin Calculator
Free online Markup Vs Margin Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Metal Cutting Speed Calculator
Free plasma, oxy-fuel, and bandsaw speed calculator. Enter material and thickness — get IPM and cut time. Not a mill SFM/RPM tool.…
Metal Gauge to Thickness Converter
Convert sheet-metal gauge to inches and mm for steel, aluminum, stainless, and galvanized. Bidirectional — gauge or decimal. Instant result.
Metal Roof Thermal Expansion Calculator
Work out how far a metal roof panel grows and shrinks over its run, how much of that movement a single clip…
Metal Roofing Panel Calculator
Metal roofing panel count and linear footage from coverage width, custom length, pitch, and waste. Not a shingle-bundle takeoff — confirm manufacturer…
Metal Weight Calculator
Use our metal weight calculator to find weight, volume, and material cost for steel, aluminum, stainless, copper, brass, and more. Use it…
Mig Welding Calculator
Free MIG welding settings calculator — enter material and thickness to get wire feed speed, voltage, and gas flow instantly. Use it…
Milling Speed and Feed Rate Calculator
Calculate milling RPM, feed rate, and chip load for any material and end mill. SFM-based milling speeds and feeds for steel, aluminum,…
Motor Circuit Sizing Calculator
Calculate motor branch circuit conductor size, OCPD rating, overload relay setting, and disconnect ampere rating per NEC Article 430. Enter HP, voltage,…
Motor Full-Load Amps (FLA) Calculator
Free motor full-load amps (FLA) calculator. Enter HP, voltage, and phase to get NEC-compliant FLA for motor circuit sizing and protection. Use…
MPG Calculator
MPG calculator: actual mpg from miles and gallons, or EPA combined mpg from city and highway using the 40 CFR 600.210-12 harmonic…
Noise Exposure Calculator
Free noise exposure calculator. Estimate allowable time, dose percent, and hearing protection need using OSHA or NIOSH criteria from dBA level and…
NPT Pipe Thread Calculator
Calculate NPT tap drill size, TPI, major/minor diameter, hand-tight L1 and wrench-makeup L2 from ASME B1.20.1 for 1/8"–4" pipe. Use it free…
Ohm’s Law & Power Calculator
Free Ohm's Law and power calculator. Solve for voltage, current, resistance, and power instantly. Essential reference for electricians and techs.
Oxy-Fuel Cutting Tip Size & Gas Pressure Calculator
Free oxy-fuel cutting tip calculator. Victor-style tip size, oxygen and fuel pressure, and travel speed by thickness and gas type. Use it…
Panel Schedule Builder Calculator
Build a full NEMA odd/even panel circuit directory. Export printable PDF, CSV, or JSON. Multi-pole spanning, connected-load tally — not an NEC…
Panel Schedule Calculator
Free panel schedule calculator for electricians. Build a complete load schedule with breaker sizing, amperage, and circuit assignments. Use it free on…
Parting & Cutoff Speed Calculator
Calculate RPM and feed rate for parting and cutoff on a lathe. Enter diameter and material — get instant speed, feed, and…
Payload Capacity Calculator
Calculate available payload remaining: GVWR minus curb, passengers, cargo, and tongue weight. Shows total payload capacity and a hard over-GVWR warning. Not…
Payroll Overtime Calculator
Free online Payroll Overtime Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Percentage Calculator
Free online Percentage Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Pipe Miter Template Generator
Free pipe miter template generator for a simple 2-piece pipe miter joint. Print a full-scale flat pattern — same tool as lobster-back…
Pipe & Tube Weight Calculator
Use our pipe tube weight calculator to find weight by material, outside diameter, wall thickness, and length. Use it free on TestTalkHQ…
Pipe Welding Calculator
Free pipe welding calculator. Enter pipe schedule, diameter, and process to get starting amperage, electrode size, bevel angle, root opening, and pass…
Plasma Cutting Calculator
Free plasma cutting speed calculator. Get recommended cut speeds for steel, aluminum, and more based on material thickness. Fast and field-ready.
Pneumatic Cylinder Air Consumption Calculator
Work out the SCFM a pneumatic cylinder really draws from bore, rod, stroke, pressure and cycle rate. Includes port tubing volume, extend…
Pneumatic Cylinder Rod Buckling Calculator
Check whether a pneumatic cylinder piston rod will buckle before you order it. Enter bore, pressure, rod diameter, stroke and how the…
Pneumatic Valve Cv Calculator
Work out the flow coefficient a pneumatic valve, quick coupler, regulator or FRL has to have to pass your air flow without…
Preheat Temperature Calculator
Free welding preheat temperature calculator using the carbon equivalent formula. Get minimum preheat by base metal chemistry, thickness, and process. AWS…
Press Brake Tonnage Calculator
Estimate press brake tonnage for air bending by thickness, bend length, and V-die opening. Capacity planning — not bend allowance or radius…
Pro Rata Refund Calculator
Free online Pro Rata Refund Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Pulley & Belt Ratio Calculator
Calculate driven pulley RPM, speed ratio, and open-belt length from driver/driven diameters and motor RPM — plus reverse mode to size a…
Rafter Length & Roof Pitch Calculator
Calculate common rafter length, roof pitch in degrees and X/12, plus plumb and birdsmouth cut angles. Enter span or run, rise or…
Reaming Speed and Feed Calculator
Calculate reaming RPM, feed rate, and stock allowance for precision hole finishing. Recommended reaming speeds for HSS and carbide reamers in steel,…
Refrigerant Charge Calculator (Line Set Length)
Calculate extra R-410A, R-22, R-32, or R-454B ounces to add for line-set length beyond the factory-charged length, plus total system charge.
Replacement Cost Estimator
Free online Replacement Cost Estimator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Residential Load Calculator
Free NEC 220.82 dwelling calculator. Enter sq ft, appliances, and HVAC — get optional-method demand amps for a house panel. Not commercial…
Respirator Cartridge Changeout Calculator
Free respirator cartridge changeout calculator. Educational service life estimate for OV, acid gas, multi-gas, and P100 cartridges with humidity and…
Ridge Cap Shingle Calculator
Ridge cap calculator: ridge + hip linear feet into hip-and-ridge bundles. Default 25 ft/bundle (GAF Seal-A-Ridge), editable coverage and waste.
Roof Pitch / Slope Calculator
Convert roof pitch as X-in-12, degrees, or percent slope. Get the roof-area multiplier and true roof square footage from plan footprint. Use…
Roof Snow Load Calculator
Convert ground snow load to balanced roof snow load with ASCE 7-16: pf = 0.7 Ce Ct Is pg, then slope factor…
Roofing Nail & Fastener Calculator
Roofing nail calculator: squares or sq ft, 3-tab vs architectural, 4-nail vs 6-nail high-wind, waste, and nail length by 7/16, 1/2, or…
Roofing Square & Shingle Bundle Calculator
Calculate roofing squares, shingle bundles, and underlayment rolls from footprint or measured area, X/12 pitch, and waste. 1 square = 100 sq…
Roofing Underlayment Coverage Calculator
Roofing underlayment calculator: felt or synthetic roll count from roof area, single vs double coverage by pitch (IRC low-slope), and waste. Ice-and-water…
Sensible Heat Ratio Calculator
Work out the sensible heat ratio and the real delivered capacity of a cooling coil from measured airflow and the dry-bulb and…
Septic Tank Sizing Calculator
Planning septic tank gallons from IPSDC Table 802.7.1 by bedrooms. Local health department code wins — more state-variable than IPC/UPC tools. Not…
Series and Parallel Circuit Calculator
Free series and parallel circuit calculator for up to 6 resistors. Total resistance, branch current, voltage drop, and formulas shown — optional…
Sheet Metal Bend Allowance Calculator
Calculate sheet metal bend allowance, bend deduction, and flat pattern length for any material, thickness, bend angle, and inside radius. Free fabrication…
Bend Deduction & K-Factor Calculator
Calculate sheet metal bend deduction and K-factor for press brake flat patterns. Distinct from bend allowance — focused on BD and K-factor…
Sheet Metal Bend Radius Calculator
Calculate the minimum inside bend radius for sheet metal by material type and thickness. Prevent cracking and springback with correct bend radius…
Shielding Gas Flow Rate Calculator
Free CFH calculator for MIG and TIG. Enter process and nozzle size — get shielding-gas flow for indoor and outdoor. Instant result,…
Short Circuit / Fault Current Calculator
Free short circuit current calculator — point-to-point f-factor method from transformer kVA, %Z, and feeder length. Compare available fault current to…
Sine Bar / Sine Plate Angle Calculator
Calculate sine bar stack height or resulting angle. H = L x sin(theta) with DMS input and suggested 81/83-piece gauge block combinations.…
Sling Angle Load Calculator
Free sling angle load calculator. Reduce rated capacity by sin(angle from horizontal), check multi-leg bridle tension, and see pass/fail against load weight.
Solar Panel Circuit Sizing Calculator
Free solar panel circuit sizing calculator. NEC 690-compliant wire gauge, breaker size, and conduit sizing for your PV system. Use it free…
Spot Welding Calculator
Calculate spot welding current, weld time, hold time, electrode force, and tip diameter by material and thickness. Covers mild steel, galvanized, stainless,…
Square-to-Round Transition Flat-Pattern Generator
Develop square, rectangular, or offset-to-round transition flat patterns by triangulation. Export DXF and a full-scale tiled PDF with reference square.
Stair Stringer Calculator
Calculate stair stringer layout: number of steps, rise and run per step, stringer length, and a typical IRC code flag (max 7.75…
Steel Beam Span / Size & Deflection Calculator
Check an AISC W-shape for bending stress and deflection, or auto-select the lightest passing shape. Simply-supported preliminary sizing with PDF and CSV…
Stick Welding Calculator
Free stick calculator. Enter electrode type, diameter, and thickness — get amps and polarity. Instant SMAW setup, no signup. Use it free…
Stud Wall Calculator
Calculate stud count, top and bottom plate lengths, and door/window king, jack, and cripple extras for 16" or 24" O.C. stud walls.…
Sub-Panel Sizing Calculator
Free sub-panel sizing calculator. Enter your loads and get the right amperage, wire gauge, and main breaker size for any detached garage,…
Sump Pump Sizing Calculator
Size a sump pump from basin diameter, inflow GPM, and total discharge head. Required GPM, 1/3–3/4 HP class, and cycle time. Starting…
Superheat / Subcooling Calculator
Calculate HVAC superheat (fixed orifice) or subcooling (TXV) from line temperature, gauge pressure, and refrigerant (R-410A, R-22, R-32) — target range…
Surface Finish Ra Calculator
Calculate theoretical surface roughness (Ra) from feed rate and tool nose radius for turning and milling. Results in microinches and micrometers with…
Tap Drill Size Calculator
Use our tap drill size calculator to find the right drill bit size for metric and imperial threads fast and without guesswork.…
Tap File Editor
Free online Tap File Editor from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link. Use it…
Tap Torque Calculator
Estimate tapping torque in in-lb or Nm by thread size, material, and tap type. Plan tap wrench and drill-press clutch settings —…
Tapping Speed and Feed Calculator
Calculate tapping RPM and cutting speed for any thread size and material. Recommended tapping speeds for HSS and spiral flute taps in…
Thread Engagement Length Calculator
Calculate the minimum thread engagement length for bolts and screws in steel, aluminum, and other materials. Ensures pull-out strength and joint safety.
Thread Pitch Calculator
Calculate thread pitch, TPI, lead, and thread angle for any imperial or metric fastener. Instant results for machinists, welders, and fabricators.
Three-Phase Power Calculator
Calculate three-phase power, current, apparent power (kVA), real power (kW), and reactive power (kVAR) for Wye or Delta systems. Enter voltage, current,…
TIG Tungsten Electrode Size & Amperage Selector Calculator
Select TIG tungsten diameter (in/mm), tip prep, and collet/cup size from amperage, DCEN/DCEP/AC, material, and electrode type — AWS A5.12 ranges.
Tig Welding Calculator
Free TIG calculator. Enter material and thickness — get amps, tungsten size, and filler. Instant setup numbers, no signup. Use it free…
Tire Size & Speedometer Error Calculator
Compare two tire sizes: overall diameter %, speedometer error at a true speed, and revs per mile. Flags changes outside the common…
Tolerance Stack-Up Calculator
Calculate worst-case and statistical (RSS) tolerance stack-up for assemblies. Add multiple dimensions with plus/minus tolerances. Use it free on TestTalkHQ o…
Towing Capacity Calculator
Calculate available towing capacity from GCWR minus curb, passengers, and cargo. Compare to the advertised tow rating. Starting point — not the…
Trailer Tongue Weight Calculator
Calculate the 10–15% trailer tongue weight target from loaded trailer weight. Compare a measured reading or estimate from cargo placement. Flags sway…
Transformer Sizing Calculator
Calculate required transformer kVA, primary and secondary full-load current, and NEC 450.3 overcurrent protection sizes for single-phase and three-phase…
Trip Fuel Cost Calculator
Calculate trip fuel cost from distance, mpg, and pump price. Gallons needed, total dollars, and cost per mile. Round-trip and commute-trip modes.
Tube Bending Calculator
Calculate arc length, bend deduction, D/t ratio, and wall thinning percentage for round tube and pipe bending. Enter OD, wall thickness, CLR,…
Tube Notch Template Generator Calculator
Generate an actual-scale wrap-around pipe/tube notch (coping) template for T-joints and angled joints. Exact cylinder-intersection math, PDF print at 100%,…
Umbrella Policy Threshold Calculator
Free online Umbrella Policy Threshold Calculator from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link.
Voltage Drop Calculator
Free voltage drop calculator for electricians. Enter wire size, length, current, and voltage to get drop percentage and NEC compliance check.
Water Heater Sizing Calculator
Size a tank water heater and first-hour rating from household size, bathrooms, peak-hour use, and gas vs electric. DOE worksheet starting point…
Water Softener Sizing Calculator
Size a salt-based water softener from household size, hardness (GPG or ppm), and iron. Daily grains, 7-day capacity, 25% reserve. Starting point,…
Water Supply Pipe Sizing Calculator
Minimum trunk/branch from IPC 2021 Table E104.1 by WSFU, length, and pressure, plus UPC Table 610.4. Prescriptive starting point — not a…
Weld Cost Calculator
Free weld-cost calculator. Enter wire, gas, labor, and arc time — get dollars per joint and per job. Built for shop bids,…
Weld Deposition Rate Calculator
Free deposition-rate calculator for MIG, FCAW, and stick. Enter WFS, wire size, and efficiency — get lbs/hr instantly. Built for shop job…
Weld Joint Design Calculator
Calculate weld joint dimensions, groove angles, root opening, and throat size for butt, fillet, and groove welds. Free tool for welders and…
Weld Quote / Job Estimate Builder Calculator
Build itemized welding job quotes with discount-before-tax totals. Export PDF, CSV, or JSON. Cost first with Weld Cost Calculator, then quote.
Weld Shrinkage & Distortion Allowance Calculator
Free weld shrinkage calculator. Estimate transverse distortion allowance by weld type, thickness, material, and number of passes for layout compensation.
Weld Symbol Builder
Free online Weld Symbol Builder from TestTalkHQ. No signup, mobile-friendly, and embeddable on your site with a dofollow attribution link. Use it…
Welder Power Cost Calculator
Free welder kWh calculator. Enter amps, volts, duty cycle, and hours — get power use and bill impact at 240V. Instant result.…
Welding Amperage Calculator
Interactive welding amperage lookup — same reference data as our MIG/TIG/Stick chart. Enter thickness, process, and material for recommended amp range.
Welding Cable Size Calculator
Size welding machine power cable by output amps and total lead length. AWS-style ampacity and voltage drop — not MIG filler wire…
Welding Fume Ventilation CFM Calculator
Free welding fume ventilation CFM calculator. Estimate local exhaust, booth, and dilution airflow for MIG, TIG, stick, flux-core, and plasma processes.
Welding Gas Cost Calculator
Free shielding-gas cost calculator. Enter CFH, cylinder price, and arc time — get $/hr and $/job for MIG and TIG. Instant result.…
Welding Rod Selection Calculator
Select base metal, thickness, position, and power source — get your primary electrode recommendation, amperage range, and storage requirements instantly.
Well Pump Sizing Calculator
Size a well pump from depth, lift, GPM, pipe, and pressure. HP and tank size. Starting point, not a pump curve. Use…
Wheel Offset & Backspacing Calculator
Convert wheel offset (mm) to backspacing (in) and back. Hub-to-inner-edge plus a rough fender vs frame clearance flag. Starting point — not…
Whole-House Ventilation CFM Calculator
Size the whole-house mechanical ventilation fan on both rate bases at once. Floor area and bedroom count give the IRC M1505.4.3 Equation…
Wire Ampacity& Derating Calculator
Free wire ampacity and derating calculator with NEC tables. Enter conductor size, insulation type, and conditions to get derated ampacity. Use it…
Wire Feed Speed to Amps Calculator
Free wire feed speed to amps calculator. Convert MIG IPM to amperage and amps to IPM using burn-off factors for mild steel,…
Wire Fill Calculator
Free wire fill calculator. Enter conduit type, size, and wire gauge to check NEC fill percentage instantly. Supports THHN, XHHW, and mixed…
Wire Gauge Calculator for Welders
Free MIG wire-diameter calculator. Enter material and thickness — get .023, .030, .035, or .045 wire. Instant shop lookup, no signup. Use…
Wire Pulling Tension Calculator
Calculate conduit pulling tension, sidewall pressure, and jam-ratio risk. Set friction for PVC/EMT/rigid, check copper max tension (6 lb/1000 cmil), and…
Wire Spool Runtime Calculator
Calculate feet of welding wire on a spool and how long a MIG or flux-core spool lasts by diameter, material, spool weight,…
WPQ Builder Calculator
Document a welder performance qualification test and export a formatted WPQ test record PDF. Save/load JSON; import a WPS export to prefill.…
WPS Builder Calculator
Fill welding parameters and export a formatted WPS template PDF. Save/load JSON drafts. Documentation template only — not a qualified WPS or…