Compared on 4 November 2026
ElecCalc vs jCalc
jCalc and ElecCalc are both web calculators for Australian and New Zealand electrical work. jCalc is built by a chartered electrical engineer and has a detailed cable sizing calculator. ElecCalc is a free suite built by a working electrician in Adelaide. This page sets out what each one offers, using what jCalc's own pages said on 4 November 2026, so you can pick the right tool for the job.
At a glance
| Feature | ElecCalc | jCalc |
|---|---|---|
| Price | Free | Calculations free. Subscription A$265 per user per year, GST inclusive, renews automatically |
| Account needed | No | Not to calculate. A log in is used for the subscription |
| PDF reports | Free on all 26 calculators, no watermark | Subscribers, on cable sizing, maximum demand and arc flash, with table and column references and custom branding |
| Saving results | Free history of up to 100 results, stored on your device | Subscribers can save and edit calculations on the jCalc server (listed for maximum demand) |
| Sharing results | Share link on every calculator that reopens your inputs | Through subscriber PDF reports. The Terms of Use restrict giving free screenshots to clients as design documentation |
| Calculators | 26 | 16 listed on the homepage |
| Cable sizing editions | AS/NZS 3008.1.1 method. Resistance and reactance from the 2009 Tables 30, 34 and 35; current ratings and derating indicative | AS/NZS 3008.1.1:2025 and 2017 (Australia), AS/NZS 3008.1.2:2017 (New Zealand) |
| Other standards | AS/NZS 3000:2018, IEEE 1584:2018, IEC 60909, IEC 60255 and IEEE C37.112, AS/NZS 4777.1:2024, AS/NZS 2293.1 | AS/NZS 3000:2018, IEEE 1584:2018 and 2002, Ralph Lee method, IEC and IEEE relay curves |
| Dark mode | Yes | No theme option on the pages we checked |
| Mobile | Responsive, and installs to your home screen to work offline | Web, with a dedicated mobile layout on maximum demand |
| Equations | Rendered on the server as text (KaTeX with MathML), with your figures substituted into each step | Typeset in the browser (MathJax), with a step by step view on cable sizing |
| Support | Corrections and questions by email | Email calculator support for subscribers, no general design support |
jCalc details are from its price page, About page, FAQ, Terms of Use and calculator pages. Prices and features change, so check jcalc.net for the current offer.
Calculator by calculator
The first 16 rows are calculations both sites offer. The rest are ElecCalc calculators with no matching page in jCalc's homepage list. Each site goes deeper on some of the shared ones than the other.
| Calculation | ElecCalc | jCalc |
|---|---|---|
| Cable sizing | Cable sizing | Yes |
| Maximum demand | Maximum demand | Yes |
| Arc flash (IEEE 1584:2018, Ralph Lee) | Arc flash | Yes |
| Solar voltage rise | Voltage rise | Yes |
| Voltage drop | Voltage drop | Yes |
| IDMT relay trip time | IDMT relay | Yes |
| Motor current | Motor calculator, Full load current | Yes |
| Motor speed | Motor speed | Yes |
| Motor torque | Motor torque | Yes |
| Transformer current and turns ratio | Transformer sizing | Yes |
| Transformer fault current | Transformer fault | Yes |
| Generator load current | Full load current, Generator sizing | Yes |
| Generator fault current | Generator fault | Yes |
| Battery size | Battery and UPS | Yes |
| Full load current | Full load current | Yes |
| Three-phase power | Three-phase power | Yes |
| Circuit breaker selection | Circuit breaker | Not listed |
| Conduit fill | Conduit fill | Not listed |
| Earth conductor sizing | Earth conductor | Not listed |
| Earthing system and earth electrodes | Earthing system | Not listed |
| Emergency lighting | Emergency lighting | Not listed |
| EV charger circuits | EV charger | Not listed |
| Lighting load | Lighting load | Not listed |
| Power factor correction | Power factor | Not listed |
| RCD selection | RCD selection | Not listed |
| Solar PV array sizing | Solar PV | Not listed |
Where jCalc is stronger
- Cable current ratings from the 2025 tables. jCalc's cable sizing calculator offers AS/NZS 3008.1.1:2025 alongside the 2017 edition. ElecCalc's cable current ratings and derating factors are still indicative working values, so for a rating you will rely on, jCalc is currently the better reference.
- A mature cable sizing calculator. It covers five phase arrangements including DC, grouping, temperature, depth and soil resistivity derating, parallel actives and earths, and protection checks for MCBs, MCCBs with let-through energy, and generic devices.
- New Zealand conditions. Cable sizing can be run to AS/NZS 3008.1.2:2017. ElecCalc does not offer the New Zealand tables.
- Method transparency. jCalc's pages explain each method, its formulas and the tables used, and its voltage rise results name the table and column behind each resistance and reactance value. Its subscriber PDF reports carry those references too.
- An engineer behind it. jCalc is owned and written by a chartered professional engineer (CPEng, Engineers Australia), and states 22,000 automated tests.
Where ElecCalc is different
- Everything is free, with no account. PDF reports, calculation history and share links work on every calculator, and the PDF has no watermark.
- More calculation types. 26 calculators, including RCD selection, earthing systems, earth conductors, conduit fill, circuit breakers, EV chargers, emergency lighting, lighting load, power factor correction and solar PV sizing.
- Working you can follow. Each calculator shows its derivation with your figures substituted into every step and cites the clause or table it uses. Results update as you type.
- Runs on your device. The calculations run in your browser, history stays on your device, dark mode is built in, and the site installs to a phone and works offline.
- Learning material. Long-form guides, practice quizzes and a capstone practice hub for apprentices.
Which should you use?
Use whichever fits the job, and there is no harm in using both. If you need cable current ratings to the 2025 tables, New Zealand cable conditions, or branded subscriber reports, jCalc does that today. If you want a free PDF, a quick check on site from your phone, or a calculation jCalc does not list, ElecCalc covers it. Running the same circuit through both is a sensible cross-check.
Whichever tool you use, it is a design aid. Check the result against the current edition of the standard and the manufacturer's data, and have it signed off by whoever is responsible for the installation.
Common questions
Is ElecCalc free?+
Yes. Every ElecCalc calculator, the PDF reports, the calculation history and the share links are free, with no account and no watermark. The site is funded by users who choose to support it. jCalc also lets you run its calculations for free, and sells an annual subscription for its PDF reports, saved calculations and email support.
Does ElecCalc have a PDF export?+
Yes, on all 26 calculators. The PDF is generated in your browser and includes your inputs, the results, the compliance checks, the step by step working and the standard references. There is no watermark and no account. On jCalc, PDF reports are a subscriber feature, and they include table and column references and custom branding.
Which standards do ElecCalc and jCalc use?+
Both work to AS/NZS 3000:2018 for maximum demand and earth cable sizing, AS/NZS 3008.1.1 for cable sizing and voltage drop, and IEEE 1584:2018 for arc flash. jCalc offers AS/NZS 3008.1.1:2025, AS/NZS 3008.1.1:2017 and AS/NZS 3008.1.2:2017 (New Zealand) on its cable sizing calculator. ElecCalc uses the AS/NZS 3008.1.1 method with resistance and reactance transcribed from AS/NZS 3008.1.1:2009 Tables 30, 34 and 35, while its cable current ratings and derating factors are labelled indicative until they are transcribed from the 2025 tables.
Is ElecCalc affiliated with jCalc?+
No. ElecCalc is built by SEY Solutions in Adelaide and has no connection with jCalc or its owner. jCalc is a trademark of its owner.
Which one should I use?+
Use whichever fits the job, or both. jCalc has the deeper cable sizing calculator with current ratings from the 2025 tables. ElecCalc covers more calculation types and gives PDF reports, history and share links for free. Whichever you use, check the result against the standard and have it signed off by whoever is responsible for the installation.