Alternator Calculator

Calculate alternator sizing and output for automotive and marine applications.

Calculation Mode

Common Load Examples

Headlights: 10-15A
Heated seats: 10-15A
Stereo system: 5-40A
Cooling fan: 15-30A
Fuel pump: 5-10A

Recommended Alternator

100
Amps

Load Analysis

Current Load80.0 A
Required (with margin)100.0 A
Power Output1120 W
Available Headroom20.0 A (20%)
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Editorial Note

MyCalcBuddy Editorial Team

This page is maintained as an educational calculator reference.

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Formula Source: Standard Mathematical References

by Various

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