Amp to Wire Size Calculator
Pick a copper wire size from the current in amps, with voltage drop for your run length.
Compare Your Options And Get Clear Answers
Pick a copper wire size from the current in amps, with voltage drop for your run length.
Amp to Wire Size Estimator
Enter your numbers below for an instant estimate.
How It Works
Key concepts behind this calculator
Enter Values
Fill in each field with your own numbers.
Calculate
Results update as you change the inputs.
Review
Read the breakdown and the explanation.
Adjust
Change values to compare scenarios.
Amp Quick Guide
Typical values for reference.
| Amps | Length m | Volts | Size |
|---|---|---|---|
| 10 | 15 | 230 | 1.0 mm2 |
| 20 | 15 | 230 | 2.5 mm2 |
| 32 | 15 | 230 | 6 mm2 |
| 50 | 15 | 230 | 10 mm2 |
| Rule of Thumb | Check inputs | Use as a guide | Round sensibly |
Amp to Wire Calculator FAQ
Answers to common questions about this calculator.
Commonly 2.5 mm2 copper, depending on installation method.
Use a qualified electrician.
Wire chosen from typical ampacity; drop = 2 x 0.017241 x length x amps / area.
It is an estimate based on the inputs you enter. Check real quotes, labels or official guidance for important decisions.