Wire Ampacity Calculator Updated!!!

This calculator uses a simplified thermal model. Results are approximations and may not match IEC/UL standards. Always verify with certified tables before real-world use.

Uses I_max = sqrt(ΔT / (R_elec · R_th)) with consistent units. Model applies to a single insulated conductor in air.

Cross-sectional area (A) — mm²

Conductor material

Insulation type

Ambient temperature (°C)

Maximum insulation temperature (°C) — editable

Insulation thickness (mm) — editable Laying / environment

Convection coefficient h (W/m²K)

Typical h: free horizontal cable ~6–12, forced/ventilated higher.

No calculation yet.

Values are per-meter; cable length cancels out.
Model is approximate and does not replace certified ampacity tables.
For multi-core, buried, conduit, or grouped cables, correction factors are required.