Enter any two of V, I, R or P and get the rest. TradeSet’s Ohm’s Law calculator works offline on site and saves results to jobs.
This calculator is one tool inside the TradeSet app: NCC stair checks, PDF export, and your last calc one tap away.
Last updated: 30 August 2026
Metric units (mm/m) are used throughout, with Australian standards context where applicable.
Fast on-page input check using metric units for planning only.
Adjusted planning quantity is 111 units (base 100 with 10% allowance).
General guidance only. Verify with plans/engineer/local requirements.
This page is one calculator from the TradeSet Toolbox. Use the app to keep calculator history, attach results to jobs, and export clean PDFs from one place.
Open another tool now so your workflow stays in the same TradeSet calculator cluster.
Voltage Drop Calculator
Single-phase voltage drop along a cable run. Copper or aluminium, metric mm².
Open toolConduit Fill Calculator
Conduit fill percentage from inside diameter and cable overall diameter.
Open toolUnit Conversions
Length, area, volume and more. Swap units in one tap.
Open toolOhm's Law & Power Calculator is built for Australian tradies who need fast, practical answers while planning work, ordering materials, or checking quantities on site.
It supports metric workflows (mm/m) and helps you move from raw measurements to usable outputs without spreadsheet delay. Use this page as an answer resource first, then as a tool.
Current is 3 A and power is 36 W.
Ohm's Law & Power Calculator gives fast planning outputs for measuring, ordering, and quoting tasks on Australian jobs in metric units.
No. Use outputs as general guidance only, then verify decisions against approved plans, engineering advice, and local requirements.
Yes. TradeSet is designed for on-site workflows where reception can be unreliable, with calculators and saved context available quickly.
Use these links to move from guide to calculator, then continue in the TradeSet app workflow.
Voltage Drop Calculator
Single-phase voltage drop along a cable run. Copper or aluminium, metric mm².
Open calculatorConduit Fill Calculator
Conduit fill percentage from inside diameter and cable overall diameter.
Open calculatorUnit Conversions
Length, area, volume and more. Swap units in one tap.
Open calculatorOutputs use metric units and are intended as general guidance for Australian site planning. Check NCC/AS and project-specific requirements for your situation.
General guidance only. Verify with plans/engineer/local requirements.