Grounding Resistance Calculator

Calculate ground rod resistance, ground grid resistance, and soil treatment requirements per IEEE 80.

Measured soil resistivity. Clay: 40-500, Sand: 1000-5000, Loam: 100-400 Ω·m.
Ω·m
Length of ground rod. Standard: 2.4m (8ft) or 3.0m (10ft).
m
Diameter of ground rod. Standard: 16mm (5/8") or 19mm (3/4").
mm
Total number of ground rods in parallel.
Distance between parallel rods. Minimum = rod length.
m

Results

Single Rod Resistance-Ω
Total System Resistance-Ω
NEC Compliance (<25Ω)-
References: IEEE 80 — Grounding; NEC Article 250