Every Free Tool on Our Site (and the 30-Second Problems Each One Solves)

What free electrical tools can you actually use before calling an electrician? Seven of them, all built by us and free on this site: a postcode checker that tells you whether Ausgrid or Endeavour Energy runs your street, calculators for maximum demand, cable sizing, EV charging and generator sizing, a pole strut calculator, and a clause finder for NSW electrical rules. Each one turns a question you would normally wait on hold for into a 30 second answer.

⚡ Quick Answers: our free tools

• Which network am I on? The postcode network checker answers it in seconds.
• Can my home handle another big appliance? The maximum demand calculator estimates your load headroom.
• What cable size does my run need? The cable size calculator works it through properly.
• What will an EV cost to charge and how fast? The EV charger calculator does both.
• What size backup generator? The generator load calculator sizes it from what you want to keep running.
• Which rulebook covers my situation? The NSW electrical rules clause finder points you to the right document.

1. The postcode network checker

Sydney splits between Ausgrid and Endeavour Energy, and which side of the boundary you sit on changes your emergency number, your connection paperwork and some of the technical rules. The network checker answers it from your postcode. If the result surprises you, our guide to telling the networks apart explains the boundary quirks.

2. The maximum demand calculator

Every “can I add an EV charger, ducted air con, pool heat pump” question is really a maximum demand question: how much load your supply can carry versus what is already on it. The maximum demand calculator gives you the estimate, and our post on load increases and NOSW paperwork explains what happens when a new appliance tips you over.

3. The cable size calculator

Long runs to granny flats, sheds and EV chargers need bigger cable than most people expect, partly for current and partly for voltage drop. The cable size calculator works through it the way an electrician would, and the background is in our cable sizing explainer.

4. The EV charger calculator

The EV charger calculator estimates charging speed and running cost for your car and tariff, which settles the single phase versus three phase question with numbers instead of guesses. Pair it with our apartment and strata EV charging page if you are in a unit.

5. The generator load calculator

Backup generators get sized from what must stay on, not from the biggest number on the brochure. The generator load calculator builds your essentials list and lands you on a realistic size before we confirm it on site. The automatic transfer switch explainer covers how the backup actually cuts in.

6. The pole strut calculator

A niche one for tradies and owners with private power poles: the pole strut size calculator works out strut sizing for pole installations, useful when a leaning pole needs proper support rather than hope.

7. The NSW electrical rules clause finder

NSW electrical work answers to several rulebooks at once: the wiring rules, the Service and Installation Rules of NSW, and each network's safety rules. The clause finder points you to the right document for your question, and our explainer on how the rulebooks fit together gives the plain-English version.

How High Demand Electrical helps

The tools give you a fast, honest starting point; the confirmation still needs eyes on your actual switchboard, cable runs and supply. That is deliberate. Use the calculators to get oriented, then bring the numbers to us and we verify them as part of a proper Level 2 assessment, whether the job is a supply upgrade, an EV circuit or a standby generator. You will find all the tools in one place on our free tools page.

Free Electrical Tools FAQs (Sydney)

Are the calculators accurate enough to buy equipment from?

They are accurate enough to plan and budget from. Final sizing gets confirmed on site because real switchboards and cable routes hold surprises.

Do the tools cost anything or need a sign-up?

No. They are free, no account needed, and they work on your phone.

Why does a maximum demand calculator appear inside some of your articles?

We embed the relevant calculator directly into posts where it answers the article's question, like our balancing of load explainer.

Can I use the tools for a property I am buying?

Yes, they are handy due diligence. Pair them with a pre-purchase electrical inspection for the full picture.

Got a number from one of the tools and want it verified? Book a Level 2 assessment or call 0402 559 777. Every job starts with a site assessment before scope and pricing are confirmed.