28 AWG Wire Size — Diameter, Ampacity & Resistance

Quick Reference — 28 AWG

Diameter: 0.0126″ (0.321 mm)
Area: 0.081 mm² (160 cmil)
Resistance: 64.9 Ω/1000ft (Cu)
Ampacity (75°C): N/AA

Common uses: Electronics, signal wiring, telecommunications, hobby/maker projects

Wire Properties

AWG Size 28 AWG
Diameter (inches) 0.0126″
Diameter (mm) 0.321 mm
Cross-sectional area 0.081 mm² (160 circular mils)
Resistance — Copper 64.9 Ω per 1000 ft @ 20°C
Resistance — Aluminum 106.0 Ω per 1000 ft @ 20°C
Weight (copper) ~0.5 lb per 1000 ft

Ampacity

28 AWG is below the NEC Table 310.16 minimum building wire size (14 AWG). It is not rated for branch circuit wiring in buildings. Used for low-voltage, signal, and electronics applications.

Nearby Sizes for Comparison

AWG Dia (in) Dia (mm) Area (mm²) Ω/1000ft Cu Ampacity 75°C
26 0.0159 0.405 0.129 40.81 —
28 0.0126 0.321 0.081 64.9 —
30 0.0100 0.255 0.0509 103.2 —

⚠️ AWG Sizing Reminder

  • In AWG, lower numbers = thicker wire. 4 AWG is much thicker than 14 AWG.
  • Each 3-gauge decrease doubles the cross-sectional area (e.g., 11 AWG ≈ 2× the area of 14 AWG).
  • Each 6-gauge decrease doubles the diameter.
  • Always follow local electrical codes — NEC values are minimum requirements.

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