🔌 Wire Gauge Calculator

Calculate wire gauge based on current and length

📏 Input Parameters

Current (A)

Wire Length (ft)

Voltage (V)

Max Voltage Drop (%)

📊 Results

Recommended Wire Gauge

12 AWG

Voltage Drop

0.36 V

📚 Understanding Wire Gauge

What is Wire Gauge?

Wire gauge (AWG - American Wire Gauge) is a standardized system for measuring wire diameter. Lower gauge numbers indicate thicker wires that can carry more current.

Why Wire Gauge Matters

Using the correct wire gauge is critical for safety and performance:

Safety: Undersized wire can overheat and cause fires
Efficiency: Proper gauge minimizes voltage drop and power loss
Reliability: Adequate wire prevents equipment malfunction
Code Compliance: Electrical codes specify minimum wire sizes

Voltage Drop

Voltage drop is the reduction in voltage along a wire due to its resistance. Keep voltage drop under 3% for most applications, 5% maximum for some cases.

Voltage Drop = Current × Resistance × 2 (for round trip)

Common Wire Gauges

18 AWG: Low-power devices, LED strips (up to 2A)
16 AWG: Light fixtures, small appliances (up to 3.7A)
14 AWG: General circuits, outlets (up to 5.9A)
12 AWG: Kitchen appliances, AC units (up to 9.3A)
10 AWG: Electric dryers, water heaters (up to 15A)

Frequently Asked Questions

What is acceptable voltage drop?

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For most applications, keep voltage drop under 3%. Critical equipment may require less than 2%, while some non-critical applications can tolerate up to 5%. Lower voltage drop means better efficiency.

Can I use a thicker wire than recommended?

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Yes, using thicker wire (lower gauge number) is always safe and reduces voltage drop. The only downsides are increased cost and reduced flexibility. Never use thinner wire than recommended.

How does wire length affect gauge selection?

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Longer wires have more resistance, causing greater voltage drop. For longer runs, you need thicker wire to maintain acceptable voltage drop. Always account for the total round-trip distance.