How it is calculated
- Estimated usable capacity = original usable capacity × reported state of health.
- Estimated range = original reference range × reported state of health.
08 · Battery health
Estimate capacity and range at a battery health level
Convert an independently reported battery state of health into proportional capacity and range estimates. This calculator cannot measure state of health from a dashboard range reading.
Your inputs
Get your result
Use your own figures or load the worked example below. All calculations stay in this browser.
This calculator cannot measure battery health. Use a qualified diagnostic report for an actual vehicle assessment.
How to use this tool
- Enter the vehicle's original usable capacity and original reference range.
- Use a state-of-health percentage from a diagnostic report, rather than the current charge percentage.
- Calculate the proportional estimates and compare them with the report's measurement conditions.
Worked example
A battery reported at 90% health
- Original usable capacity
- 75 kWh
- Reported state of health
- 90 %
- Original reference range
- 450 km
Expected result 67.5 kWh usable capacity · 405 km proportional range
75 × 0.90 = 67.5 kWh and 450 × 0.90 = 405 km. Both outputs use the same proportional assumption.
Transparent estimates
How to read this result
A proportional estimate does not diagnose cell balance, charging performance or warranty eligibility. Real range also depends on consumption and temperature.
Assumptions
- The reported state-of-health value is treated as an accurate proportional measure of remaining capacity.
What this estimate cannot tell you
- State of health does not by itself capture cell imbalance, power limits, temperature behavior, or warranty eligibility.