Skip to content
AmpSize

Facts checked · 1 min read

jCalc and AmpSize

jCalc and AmpSize compared as cable size calculators for NZ and AU: editions cited, price, reports and guides, each fact with its source and date.

What jCalc does well

  • jCalc has 16 calculators, including cable size, maximum demand, arc flash and voltage rise. (opened)
  • Its cable size page names AS/NZS 3008.1.1:2025, 3008.1.1:2017 and 3008.1.2:2017. (opened)
  • One page holds the inputs, the defaults and the formulas. It takes A, kW, kVA or hp, and offers parallel sets and many conductor and installation choices. (opened)
  • The free version calculates without an account. (opened)

The facts side by side

jCalc and AmpSize, with the source and the date of each fact
FactjCalcAmpSize
Calculators16 (opened)53 (measured)
GuidesNo guide section linked from the home page. Method notes sit on each calculator page. (opened)25 worked guides published (measured)
AS/NZS 3008 edition citedAS/NZS 3008.1.1:2025 and 2017, AS/NZS 3008.1.2:2017 (opened)AS/NZS 3008.1.2:2017, 3008.1.1:2025, 3008.1.1:2017 (measured)
PriceFree version. A paid subscription adds save, open and report lists. (opened)Free. Pro is NZ$5 a month or NZ$45 a year. (measured)
PDF or reportA report on the free version carries a watermark. A subscription removes it. (opened)Free. PDF reports with an AmpSize footer line. (measured)
NZ part 3008.1.2Yes, 3008.1.2:2017 (opened)Yes, 3008.1.2:2017 (measured)
Mobile appNone found on the home page (opened)Android, in closed testing on Google Play (measured)

A mark after each fact says how it was read: O opened, S snippet, M measured. How to read the marks

Where AmpSize differs

  • AmpSize has 25 worked guides. Each runs one circuit and names the table behind each step.
  • The AmpSize free plan gives PDF reports with an AmpSize footer line.
  • AmpSize has a plan builder. It counts the rooms and devices on a plan into circuits and a schedule.
  • AmpSize has 53 calculators.

Which to use

Use jCalc for one circuit with the load in kW, kVA or hp.

Use jCalc when you need parallel sets or its range of construction choices.

Use jCalc when you want the formulas and the inputs on the same page as the result.

Use AmpSize when you want a worked example of the same kind of circuit.

Use AmpSize for a free PDF report with only a footer line, or a plan for a house.

Read next

Was this useful?

A question, or a value that looks wrong? Contact us.