Battery runtime
Estimate ideal runtime from battery energy, usable capacity, efficiency and load.
Your inputs
The editable example is illustrative. Enter your own dimensions, operating data, prices, and fees. Results update as you edit.
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Your result
Complete the inputs to see your result.
How it works
- Usable delivered energy = Rated capacity × Usable fraction (0–1) × Conversion efficiency (0–1); Estimated runtime = Usable delivered energy (Wh) ÷ Constant load (W); Rated capacity = Nominal voltage × Ah
- Worked example: 500 Wh × 0.8 × 0.9 = 360 Wh; 360 Wh /100 W = 3.6 h
- Supported input limits: Rated capacity: 0 ≤ x ≤ 1000000000000; Nominal voltage: 1e-12 ≤ x ≤ 1000000000000; Ampere hours: 0 ≤ x ≤ 1000000000000; Usable fraction (0–1): 0 ≤ x ≤ 1; Conversion efficiency (0–1): 0 ≤ x ≤ 1; Constant load: 1e-12 ≤ x ≤ 1000000000000
Assumptions and limitations
Prices, power, utilization and fees are your assumptions. Battery runtime assumes a constant load and known voltage for Ah. These estimates do not imply market, tax, wiring or safety recommendations.
Sources
- EIA — watts and watt-hours Sources reviewed: 2026-10-06
