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How much range will the battery keep?
Pick a published degradation rate or enter your own. This is an illustration of the arithmetic, not a prediction for any one battery.
Inputs
Starting values are illustrative, not current prices or specifications. Replace each with your own.
Result
Answer
Geotab's 2025 analysis of 22,700 EVs found an average loss of 2.3% of capacity per year, which leaves about 81.6% after eight years. A 400 km car would then have about 326 km of range. Individual batteries vary.
Worked example
At 2.3% a year, 8 years removes 8 × 2.3 = 18.4% of capacity, leaving 81.6%. A 400 km car keeps 400 × 0.816 = 326 km, and a 75 kWh battery holds 61.2 kWh. At the 1.5% rate (DC fast charging on under 12% of sessions) the same 8 years leaves 88%; at 3.0% it leaves 76%.
Formulas and notes
- State of health after n years = 1 − annual loss % ÷ 100 × n (a straight line, which matches how Geotab projects 81.6% after eight years at 2.3%).
- Range left = range when new × state of health; capacity left = battery kWh × state of health.
- Real batteries do not follow a straight line exactly, and the rate depends on climate, charging habits and the model. Geotab also reports hot climates add about 0.4% a year.
- This is an illustration, not a warranty. Check the manufacturer's battery warranty terms for coverage.
Planning estimate only, not professional advice. Sources, checked 2026-10-08: Geotab, EV Battery Health: Key Findings from 22,700 Vehicle Data Analysis (Apr. 28, 2026)
FAQ
How fast do EV batteries degrade?
Geotab's 2025 analysis of 22,700 EVs found an average of 2.3% of capacity lost per year. Its earlier 2023 analysis of 11 common models found 1.8% a year.
Does DC fast charging damage the battery?
Geotab's 2025 analysis: vehicles that DC fast charge on more than 12% of sessions, with over 40% of those sessions above 100 kW, averaged 3.0% a year, versus 1.5% for vehicles that DC fast charge on under 12% of sessions.
How much range will an EV have after 8 years?
At the 2.3% average, about 81.6% of the original. A car with 400 km of range would have roughly 326 km. Use the calculator for your own range and rate.
Does hot weather affect degradation?
Geotab reports vehicles in hot climates degrade about 0.4% per year faster than those in mild climates. Add that to your custom rate to see the effect.
Is this a prediction for my car?
No. It applies one steady rate to show what a loss rate means in range. Your battery's actual health depends on the model, climate and use; read it from the car's battery health screen where available.