EV Battery Degradation Calculator

How long will an electric vehicle battery actually last? This is a common question among those considering switching to this mode of transportation.

While an electric car can travel hundreds of kilometers without recharging, its range decreases over time. The main reason is battery degradation, or the gradual loss of battery capacity.

With our free online tool, you can calculate the remaining capacity of your electric vehicle’s (EV) or plug-in hybrid’s (PHEV) high-voltage battery.

EV Battery Degradation Calculator

Estimate your electric vehicle’s current battery health and remaining range.

Original Range (km)

Current Range (km)

Battery Capacity (kWh)

Vehicle Age (years)

Battery Chemistry

⚠ Please fill in all fields. Current range must be less than or equal to original range.

Results

        Battery State of Health (SoH)
        —
      

Health visualised

Range lost —

Usable capacity now —

Avg. yearly degradation —

Warranty threshold (70%) —

Est. years to 70% SoH —

Battery condition —

The EV Battery Degradation Calculator determines the percentage of the EV’s remaining battery capacity relative to its original capacity and estimates the rate of degradation based on mileage.

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Formula used

The calculator is built on three core equations:

1. State of Health (SoH)

SoH (%) = (Current Range ÷ Original Range) × 100

Range is the most practical real-world proxy for battery health — it reflects actual capacity better than voltage alone.

2. Usable capacity remaining

Usable kWh = Battery Capacity × (SoH ÷ 100)

3. Annual degradation rate

Annual Degradation (%/yr) = (100 − SoH) ÷ Vehicle Age

From that, it linearly projects how many years remain before hitting the common 70% warranty threshold.