100 Amp Wire Size Calculator
Pick a copper or aluminium wire size for a 100 amp service or subpanel. Preliminary only, follow local code.
Compare Your Options And Get Clear Answers
Pick a copper or aluminium wire size for a 100 amp service or subpanel. Preliminary only, follow local code.
100 Amp 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
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100 Quick Guide
Typical values for reference.
| Load | Copper | Aluminium | Note |
|---|---|---|---|
| 60 A | 6 AWG copper | 4 AWG aluminium | Typical, check code |
| 100 A | 1 AWG copper | 1/0 AWG aluminium | Typical, check code |
| 125 A | 1/0 AWG copper | 2/0 AWG aluminium | Typical, check code |
| 150 A | 2/0 AWG copper | 3/0 AWG aluminium | Typical, check code |
| Rule of Thumb | Check inputs | Use as a guide | Round sensibly |
100 Amp Wire Calculator FAQ
Answers to common questions about this calculator.
Typically 1 AWG copper or 1/0 aluminium by common tables, but local code applies.
Electrical work should be done by a licensed electrician.
Conductor chosen from typical ampacity tables; voltage drop = 2 x resistivity x length x current / area.
It is an estimate based on the inputs you enter. Check real quotes, labels or official guidance for important decisions.