Decisions for the trades, not just numbers.

Put in your conditions and get a real recommendation: the size or the option that makes sense, why it makes sense, the alternatives, the tradeoffs, and a record you can copy, print, or share. It runs in your browser. No account, no sign-up.

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Electrical (5)

Wire Size and Voltage Drop Pick a conductor size and material for a run, and know whether ampacity or voltage drop is really driving it. Breaker and OCPD Sizing Size the breaker for a load and its conductor, and see what the code rules actually require. Voltage Drop Remedy Your run drops too much voltage. See the ways to fix it and which one makes sense. Conduit Fill Pick a conduit size for a bundle of conductors and see how much room is left for future pulls. Box Fill Figure the required box volume for your conductors and devices, and pick a box that fits.

Plumbing (5)

Water Pipe Sizing Size a water supply line so the far fixture still gets the pressure and flow it needs. Drain Sizing Add up the fixtures and size a drain branch or building drain, with the water-closet and slope rules built in. Water Heater Sizing Decide between a tank and a tankless water heater for your peak demand and climate. Gas Pipe Sizing Size a natural gas line for the appliance load and run, with a plain warning that gas work is for a licensed pro. Pipe Friction Loss Find the real pressure loss down a pipe run, fittings included, and whether the size holds up.

HVAC (2)

HVAC Load Sanity Check Sanity-check a quoted air conditioner or furnace size before you commit, and know when you need a real Manual J. Duct Sizing Size a round duct for an airflow and see the velocity, with a quieter size up.

Concrete (1)

Concrete Volume and Order Work out how much concrete a pour needs, then decide whether to bag it or order ready-mix.

Next up

HVAC Equipment vs load match on the way

HVAC Static pressure budget on the way

Solar String sizing (temp-corrected) on the way

Why a workbench and not a calculator

Most trade calculators hand you a number and stop. A real job needs a decision. Which wire, which pipe, order the ready-mix or bag it, and why. TradesWorkbench is built around that second question. Every tool shows the reasoning and the tradeoffs so you can stand behind the call and explain it to whoever asks.

These are planning tools. They do not replace a licensed professional, a permit, or an inspection, and they do not certify code compliance.