Is this calculation free and private?

Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.

What does the Wire Gauge & Voltage Drop Calculator (AWG) give me?

It works out Suggested Wire Size, Voltage Drop, Actual Voltage Drop and Delivered Voltage at Load, updating live as you change the inputs.

What do I need to enter?

Just Current Load, Circuit Voltage, One-Way Cable Distance and Max Allowable Voltage Drop. Every field has a sensible default you can start from.

Is my data uploaded anywhere?

No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.

Does it work on a phone?

Yes. The layout adapts to small screens and needs no app or signup.

Wire Gauge & Voltage Drop Calculator (AWG)

Determine recommended copper American Wire Gauge (AWG) size for a given circuit amperage, voltage, and length to keep voltage drop under 3%.

100% free
Private in browser
No signup
No watermarks

Current Load (Amperes)

Circuit Voltage (Volts)

One-Way Cable Distance (Feet)

Max Allowable Voltage Drop (%)

Suggested Wire Size (AWG)

Voltage Drop (Volts)

2.29

Actual Voltage Drop (%)

1.9

Delivered Voltage at Load (Volts)

117.71

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About Wire Gauge & Voltage Drop Calculator (AWG)

Determine recommended copper American Wire Gauge (AWG) size for a given circuit amperage, voltage, and length to keep voltage drop under 3%. Enter Current Load, Circuit Voltage and One-Way Cable Distance and the tool works out Suggested Wire Size, Voltage Drop and Actual Voltage Drop straight away. Everything runs in your browser, so your data never leaves your device.

How to use Wire Gauge & Voltage Drop Calculator (AWG)

Enter Current Load, Circuit Voltage and One-Way Cable Distance.
Adjust the remaining options (Max Allowable Voltage Drop) to match your case.
Read Suggested Wire Size, Voltage Drop and Actual Voltage Drop in the results panel — copy or download what you need.

Key features

Shows Suggested Wire Size (AWG)
Shows Voltage Drop (Volts)
Shows Actual Voltage Drop (%)
4 adjustable inputs, results update as you type
No signup, no limits

Frequently asked questions

Is this calculation free and private?: Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.
What does the Wire Gauge & Voltage Drop Calculator (AWG) give me?: It works out Suggested Wire Size, Voltage Drop, Actual Voltage Drop and Delivered Voltage at Load, updating live as you change the inputs.
What do I need to enter?: Just Current Load, Circuit Voltage, One-Way Cable Distance and Max Allowable Voltage Drop. Every field has a sensible default you can start from.
Is my data uploaded anywhere?: No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.
Does it work on a phone?: Yes. The layout adapts to small screens and needs no app or signup.

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