WireSizing.com is a free wire gauge reference and sizing tool. All wire specifications on this site are calculated from published standards and formulas — no data is copied from other sources.
Our calculations are based on the following standards and references:
AWG Dimensions: ASTM B258 — Standard Specification for Standard Nominal Diameters and Cross-Sectional Areas of AWG Sizes of Solid Round Wires Used as Electrical Conductors
Ampacity: NEC (NFPA 70) Table 310.16 — Allowable Ampacities of Insulated Conductors
Metric Sizes: IEC 60228 — Conductors of Insulated Cables
Resistivity: ASM International Metals Reference Book, CRC Handbook of Chemistry and Physics
Wire Properties: Calculated from first principles using material resistivity, density, and geometric formulas
AWG Diameter: d(n) = 0.005 × 92(36−n)/39 inches
Cross-sectional Area: A = π/4 × d²
Resistance: R = ρ × L / A (where ρ = resistivity)
Voltage Drop: Vdrop = 2 × I × R × L (single phase)
Weight: W = A × ρmaterial × L
Skin Depth: δ = √(ρ / (π × f × μ0))
This site is for informational and reference purposes only. It is not a substitute for professional electrical engineering advice. Always consult a licensed electrician and follow local building codes and the National Electrical Code (NEC) for actual electrical installations.
Ampacity values shown are based on specific conditions (30°C ambient, not more than 3 current-carrying conductors in raceway). Actual ampacity may be lower due to ambient temperature, conduit fill, bundling, and other derating factors per NEC 310.15.
Questions, corrections, or suggestions? Email us at info@wiresizing.com.