Built for the field. No signup. No paywalls.

Free calculators and references for the trades.

Pipe weight. Concrete yardage. Wire size. Bolt torque. Board feet. Everything you'd otherwise be googling on a ladder — in one place, mobile-first, fast.

// Calculators

Pick your tool.

Every calculator is single-page, mobile-friendly, and works offline once loaded. Inputs in feet, inches, mm, or fractions — your call.

Pipe Weight Calculator

Weight per foot for steel, stainless, copper, and PVC pipe — Sch 10 through XXS.

CalculatorPipe

Pipe Volume Calculator

Fluid capacity in gallons, liters, and cubic feet for any pipe size and length.

CalculatorPipe

Tube Bend Calculator

Developed length, bend allowance, and springback for hand- and machine-bent tube.

CalculatorTubing

Tube Bending Fan

Kick angles, travels, and rises for every tube in a multi-tube rack. Symmetric pairs grouped automatically.

CalculatorTubing

Pipe Pressure Drop

Darcy-Weisbach pressure loss for water and common fluids over a straight pipe run.

CalculatorPipe

Flange Bolt Torque

Per-bolt torque for ASME B16.5 flanges — B7, B8M, B16, lubricated or dry.

CalculatorBolting

Wire Size Calculator

NEC-compliant ampacity sizing for copper and aluminum conductors, THHN/THWN.

CalculatorNEC

Voltage Drop Calculator

One-way and round-trip voltage drop for any wire size, length, and load.

CalculatorNEC

Conduit Fill Calculator

EMT, IMC, RMC, and PVC fill per NEC Chapter 9 — 40%, 31%, 53% rules built in.

CalculatorNEC
Ω

Ohm's Law Calculator

Solve for volts, amps, ohms, or watts — any two values give you the other two.

CalculatorElectrical

Concrete Volume Calculator

Cubic yards, cubic feet, and 80-lb bag count for slabs, footings, columns, and post holes.

CalculatorConcrete

Rebar Weight & Cut List

Weight per foot for #3 through #11 rebar plus a grid-pattern cut list generator.

CalculatorConcrete

Mortar / Brick / Block

Brick and CMU count plus mortar bags for a given wall area, with 5% waste built in.

CalculatorMasonry

Stair Stringer Calculator

Rise, run, and stringer length for code-compliant stairs — IRC 7-3/4 max rise, 10 min tread.

CalculatorFraming

Rafter / Roof Pitch Calculator

Common rafter length, plumb and seat cuts for any pitch from 1/12 through 12/12.

CalculatorFraming

Board Foot Calculator

Lumber board feet from thickness × width × length, with piece count and waste factor.

CalculatorLumber
¼

Decimal / Fraction Converter

Inches and feet — decimal to fractions (to 1/64) and back. Tape-measure friendly.

CalculatorConverter

Welding Amperage Calculator

Recommended amperage and heat input for stick, MIG, and TIG by electrode and thickness.

CalculatorWelding

Duct Sizing (Equal Friction)

Round and rectangular duct size from CFM target and friction rate.

CalculatorHVAC

Paint Coverage Calculator

Gallons needed for any wall area with primer pass, second coat, and waste factor.

CalculatorPainting

Sling Angle / Load Calculator

Sling tension at any angle for two- and four-leg picks. With OSHA D/d ratio reminders.

CalculatorRigging

Beam Load / Deflection

Simply supported beam — max moment, shear, and deflection for point and distributed loads.

CalculatorMech

Hydraulic Cylinder Calculator

Extension and retraction force, flow rate, and cycle time from bore, rod, and pressure.

CalculatorHydraulics

Cv Valve Sizing Calculator

Required flow coefficient for control valve sizing — liquids and gases. ISA-75.01 formula.

CalculatorProcess

Transformer kVA Calculator

Required kVA from load amps and voltage, or secondary amps from a known kVA rating. NEC 450.3 OCPD sizing.

CalculatorElectrical

Motor FLA Calculator

Full load amps per NEC 430.248 / 430.250 — plus branch circuit conductor and OCPD sizing.

CalculatorNEC

Plywood / Sheet Goods Calculator

Sheet count for plywood, OSB, drywall, or any panel material — with waste factor.

CalculatorLumber

Pipe Schedule Chart

OD, wall, ID, weight for every pipe size from 1/8" through 24", Sch 5 through XXS.

ChartReference

Bolt Grade Chart

SAE Grade 2/5/8, ASTM A193 B7/B8M/B16, and metric 8.8/10.9/12.9 — proof load and tensile.

ChartReference

ASME B16.5 Flange Dimensions

Bolt circle, bolt count, OD, raised-face dimensions for 150# through 2500# flanges.

ChartReference

Drill & Tap Size Chart

Tap drill sizes for UNC, UNF, and metric threads — 50%, 65%, 75% thread engagement.

ChartReference

Steel W-Shape (I-Beam) Chart

AISC wide-flange dimensions and properties — Sx, Ix, weight, and depth for common W shapes.

ChartReference

Compression Fitting Chart

Nut hex, body hex, makeup turns, and pressure ratings for 1/8" through 1" OD tube fittings.

ChartTubing

Construction Form Generator

Print-ready JHA, toolbox talk, timesheets, inspection checklists, work orders, and more — blank or fill-in-the-field.

GeneratorForms
// Field Guides

Read this before lunch.

Short, no-fluff guides on the stuff that actually trips people up in the field.