ElecCalc.au

25 Free Australian Electrical Calculators

// the problem

Australian electricians need standards-compliant calculators for cable sizing, voltage drop, arc flash, earthing and the rest of it. Existing tools are either US-focused, behind a paywall, locked behind a login, or written against superseded standards.

// the solution

ElecCalc.au is 25 calculators built for Australian and New Zealand standards, free with no paywall, no subscription and no login. It installs from the browser as a PWA and works offline on site, and it keeps a history of your calculations.

// what is in it

The 25 calculators sit in six groups: Core calculations (6) for cable sizing, voltage drop, maximum demand and the everyday work. Protection and safety (5) covering fault loop, discrimination and arc flash. Solar and EV (3) for inverter and charger installs. Motors and power (6). Transformers and generators (3). Lighting and backup (2).

// standards

Calculations are written against AS/NZS 3008.1.1:2025 for cable sizing, AS/NZS 3000:2018 for wiring rules, AS 2053 for conduit, AS/NZS 4777.1:2024 and 4777.2 for grid-connected inverters, AS/NZS 3001.1 for EV supply equipment, AS 62040 for UPS, IEEE 1584:2018 for arc flash, and the relevant IEC standards for protection and machines.

The calculator engine is shared with [SparkyToolkit](/projects/sparkytoolkit/), the iOS companion, so the same numbers come out on the bench and in the field.

// core features

25 Calculators

Six groups: core calculations, protection and safety, solar and EV, motors and power, transformers and generators, lighting and backup.

No Paywall, No Login

Every calculator is free. No subscription, no account, no trial.

Current Standards

AS/NZS 3008.1.1:2025, AS/NZS 3000:2018, AS/NZS 4777, AS/NZS 3001.1, IEEE 1584:2018 and the relevant IEC standards.

Offline PWA

Install from your browser and it works without internet on site.

Calculation History

Keeps what you have worked out, so you can go back to it.

Shared Engine