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)

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

Plumbing (5)

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

HVAC (4)

HVAC 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. HVAC Duct Sizing Size a round duct for an airflow and see the velocity, with a quieter size up. HVAC Equipment vs Load Match Check whether an AC or heat pump size fits your load under the ACCA Manual S limits, or is oversized. HVAC Static Pressure Budget See how much static pressure your blower has left for the ducts after the filter, coil, and grilles.

Concrete (2)

Concrete Concrete Volume and Order Work out how much concrete a pour needs, then decide whether to bag it or order ready-mix. Concrete Rebar Quantity and Spacing Take off the rebar for a slab: bar count each way, linear feet with laps, and sticks to buy.

Roofing (1)

Roofing Roofing Squares and Waste Turn a roof footprint and pitch into squares and bundles, with the right waste for the roof.

Painting (1)

Painting Paint Coverage and Primer Work out gallons and coats, and whether you actually need primer for your surface and color change.

Drywall (1)

Drywall Drywall Sheets and Materials Take off drywall: sheets, joint compound, tape, and screws, and whether to run 4x8 or 4x12.

Flooring (1)

Flooring Flooring Coverage and Waste Turn a room area and layout pattern into flooring boxes to buy, with the right waste and attic stock.

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.