16 AWG Wire Specs
Ampacity, geometry, resistance, conduit fill and maximum run length for 16 AWG conductors in copper and aluminium.
Quick answer
16 AWG copper carries about 13 A at 75 °C (11 A at 60 °C, 15 A at 90 °C). The bare conductor is 0.0508 in (1.29 mm) and 2,583 circular mils, with 4.0151 Ω per 1000 ft.
Copper 75 °C
13A
Aluminium 75 °C
10A
Diameter
0.0508in
Circular mils
2,583
Full specification
| Size designation | 16 AWG |
|---|---|
| AWG gauge number | 16 |
| Circular mils | 2,583 |
| kcmil | 2.58 |
| Bare diameter (in) | 0.0508 |
| Bare diameter (mm) | 1.290 |
| Cross-section (mm²) | 1.31 |
| THHN/THWN-2 OD (in) | 0.096 |
| Insulated area (sq in) | 0.0072 |
| Copper resistance (Ω/1000 ft) | 4.0151 |
| Aluminium resistance (Ω/1000 ft) | 6.5815 |
| Max standard breaker (Cu, 75 °C) | Below branch-circuit ratings |
Published standard — source: Geometry computed from the ASTM B258 AWG formula; resistance from standard resistivityFormula estimate — source: Ampacity from the site model
Ampacity with derating
Estimated ampacity from the 90 °C column at various ambient temperatures and conductor counts.
| Conductors in raceway | 30 °C ambient | 40 °C ambient | 50 °C ambient | 60 °C ambient |
|---|---|---|---|---|
| 3 | 15 A | 14 A | 12 A | 11 A |
| 6 | 12 A | 11 A | 10 A | 8 A |
| 9 | 11 A | 10 A | 9 A | 7 A |
| 15 | 8 A | 7 A | 6 A | 5 A |
| 25 | 7 A | 6 A | 6 A | 5 A |
Source & method: The governing value is also capped by the termination rating, commonly 75 °C, which for this size is 13 A. Run your own conditions.
Maximum run length at 3% voltage drop
One-way distance for 16 AWG copper before drop exceeds 3%.
| Load | 120 V 1Ø | 240 V 1Ø | 208 V 3Ø | 480 V 3Ø |
|---|---|---|---|---|
| 10 A | 36 ft | 72 ft | 72 ft | 166 ft |
| 15 A | 24 ft | 48 ft | 48 ft | 110 ft |
| 20 A | 18 ft | 36 ft | 36 ft | 83 ft |
| 30 A | 12 ft | 24 ft | 24 ft | 55 ft |
| 40 A | 9 ft | 18 ft | 18 ft | 41 ft |
| 50 A | 7 ft | 14 ft | 14 ft | 33 ft |
How many 16 AWG conductors fit in conduit
Maximum count of this size alone, at the fill percentage matching the resulting count.
| Conduit | 1/2" | 3/4" | 1" | 1-1/4" | 1-1/2" | 2" | 2-1/2" | 3" | 3-1/2" | 4" |
|---|---|---|---|---|---|---|---|---|---|---|
| EMT | 16 | 29 | 47 | 82 | 112 | 185 | 323 | 400 | 400 | 400 |
| IMC | 18 | 32 | 52 | 91 | 122 | 200 | 283 | 400 | 400 | 400 |
| RMC | 17 | 30 | 49 | 84 | 114 | 188 | 268 | 400 | 400 | 400 |
| PVC Sch 40 | 15 | 28 | 45 | 80 | 109 | 181 | 259 | 400 | 400 | 400 |
| PVC Sch 80 | 12 | 22 | 38 | 68 | 94 | 158 | 227 | 356 | 400 | 400 |
Neighbouring sizes
Frequently asked
- How many amps can 16 AWG wire carry?
- 16 AWG copper is estimated at 11 A at 60 °C, 13 A at 75 °C and 15 A at 90 °C, at 30 °C ambient with no more than three current-carrying conductors. Aluminium of the same size is about 10 A at 75 °C.
- What breaker size goes with 16 AWG copper?
- 16 AWG is below the smallest standard branch-circuit device rating and is normally used for control, signal or fixture wiring rather than a protected branch circuit.
- What is the diameter of 16 AWG wire?
- The bare conductor is 0.0508 inches (1.290 mm) in diameter, which is 2,583 circular mils. With THHN/THWN-2 insulation the nominal outside diameter is about 0.096 inches.
- What is the resistance of 16 AWG wire?
- About 4.0151 ohms per 1000 feet for copper and 6.5815 ohms per 1000 feet for aluminium, at 75 °C.
- How far can I run 16 AWG wire?
- Distance depends on load and voltage. At 20 A on a 120 V single-phase circuit, 16 AWG copper stays under 3% voltage drop for about 18 feet one-way. Doubling the voltage roughly doubles the allowable distance.
Materials for this size
Materials for this size
Wire, cable and terminations for 16 AWG.
- THHN/THWN-2 16 AWG copper16 AWG copperBuilding wire in the size this page covers (16 AWG copper).Check price on Amazon →
- NM-B cable 16 AWG16 AWGRomex-type cable for dry indoor branch circuits at this size.Check price on Amazon →
- Wire connectors for 16 AWG16 AWGPush-in or twist-on connectors rated for this conductor size.Check price on Amazon →
- Terminal lugs & anti-oxidantCopper-rated mechanical lugs for panel and disconnect terminations.Check price on Amazon →
Links go to Amazon search results, not a single listing — confirm ratings, insulation type and listing details before buying, and make sure the part is approved for your application.
Related charts & calculators
- Voltage Drop CalculatorPercent drop, end voltage and minimum conductor for any run length.
- Conduit Fill CalculatorFill percentage and maximum conductor count for EMT, RMC, IMC and PVC.
- Breaker Size CalculatorOvercurrent device rating and minimum conductor from load current.
- Wire Ampacity CalculatorDerated ampacity for ambient temperature and bundled conductors.
- Box Fill CalculatorVolume allowances for conductors, clamps, devices and grounds per NEC 314.16.
- Ampacity ChartEstimated allowable ampacity by conductor size, material and insulation rating.