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Electrical Power Calculator
Calculate your electrical system's capacity to support your amplifiers
Alternator(s)
Using default: 0 A (engine-off / battery-only)
Use your alternator's rated output, not max output
Batteries
Ah×
System Settings
Target Power (Optional)
Enter your amplifier's RMS power to see if your electrical can support it
Watts RMS
Empty = no target analysis
Electrical Capacity
Continuous PowerSUSTAINABLE
0 W
0 A × 14.4V × 80% eff
Burst Power (1 min)SHORT TERM
749 W
65 A total (alt + battery burst)
Alternator Output:0 A
Total Battery Capacity:65 Ah
Battery Burst Current:65 A
lead:65 Ah
BIG 3 UPGRADE REQUIRED
For systems over 1000W, upgrade these cables to 1/0 or 4 AWG:
- Alternator positive → Battery positive
- Battery negative → Chassis ground
- Engine block → Chassis ground
MAKING SENSE OF IT
Continuous reflects steady-state output from your alternator(s)—the ceiling for sustained RMS draw.
Burst factors in battery discharge during transient peaks. Lithium chemistries dump current far faster than lead-acid, so burst numbers climb.
Headroom (20%) keeps voltage stable when the bass drops. Without it, lights dim and amps clip.