Battery Runtime Calculator
Battery Runtime Calculator lets you estimated runtime divides usable watt-hours by constant load watts. Enter your own values or load the worked example.
- Copy or download the computed result
- Adjust capacity (ah)
- See the processing method and limits
Method and calculation
Estimated runtime divides usable watt-hours by constant load watts.
Inputs and settings
Battery Runtime Calculator accepts Capacity (Ah) (minimum 0.000001); Voltage (V) (minimum 0.000001); Load (W) (minimum 0.000001); Usable efficiency (%) (minimum 1, maximum 100).
Worked example
Battery Runtime Calculator example — Capacity (Ah): 10; Voltage (V): 12; Load (W): 20; Usable efficiency (%): 85. Computed output: { "wattHours": 120, "hours": 5.1 }
Output and limitations
Battery Runtime Calculator: Estimate excludes temperature, ageing and load-dependent discharge behaviour.
Technical references: JavaScript numerical operations
Battery Runtime Calculator FAQs
Battery Runtime Calculator applies the following rule to your input: Estimated runtime divides usable watt-hours by constant load watts. The worked example on this page uses the same processor as the result button.
Battery Runtime Calculator has these boundaries: Estimate excludes temperature, ageing and load-dependent discharge behaviour. Start by checking the capacity (ah) field against the units or format shown.
Battery Runtime Calculator provides this sample: { "wattHours": 120, "hours": 5.1 }. Use the sample button to reproduce it, then replace the inputs with your own values.