About the C-Rate Calculator
Battery C-rate from current and capacity, with the charge or discharge time it implies.
Also known as: c rating battery, discharge rate calculator, battery c rate, charge rate calculator.
How to use this calculator
- Enter calculate, capacity.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
C-rate = current ÷ capacity in Ah
Worked example
Using the values pre-filled in the calculator above:
- Calculate: C-rate
- Capacity = 100 Ah
- Current = 50 A
the calculator returns:
- C-rate: 0.5 C
- Current: 50 A
- Full discharge time: 2 hours
- In minutes: 120