Event Horizon Calculator

Calculate event horizon properties of black holes

0 = Schwarzschild, 1 = maximally rotating Kerr

Results

Enter values to calculate

Formulas

Schwarzschild: rs = 2GM/c²

Kerr horizons: r± = rg(1 ± √(1-a²))

Where rg = GM/c² and a is the dimensionless spin parameter.

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Editorial Note

MyCalcBuddy Editorial Team

This page is maintained as an educational calculator reference.

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Formula Source: University Physics

by Young & Freedman

🔄Last reviewed: May 2026
✓Formula checks are based on standard references and internal QA review.