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Used EV battery health estimator
Last updated · 35 models · 310 sourced data points
Choose a model and enter the mileage (and age, if you know it). We show the battery state of health (SoH) range that published data suggests for that car, how we worked it out, the sample size and every source.
How the estimate is worked out
- Model data first. We take every multi-car figure published for the model (for example AVILOO's medians at 50,000, 100,000 and 150,000 km, or Swedish dealer averages). For each dataset we read off the value at your mileage by straight-line interpolation between its published points. We never extend a dataset more than 25,000 km beyond its last point.
- Expected range. The typical value is the median of those dataset values. Where a dataset publishes a spread (AVILOO's band covering 99% of tested cars), that band is the range; otherwise the range is the spread between datasets.
- Thin data. If no multi-car figure covers your mileage, we use single cars (owner reports, single-car tests, listings) within ±30,000 km (±50,000 km if fewer than 3), and only if there are at least 3. The result is labelled low confidence.
- Fallbacks. Next we use other models from the same brand. After that we use all-EV benchmarks: the UK median and middle 50% by age (Generational, if you enter an age), then the Swedish all-model average by mileage (Carla).
- Context. Every result also shows nearby single cars, age-based figures for the model (such as Recurrent's US range retention, which measures range, not capacity) and all-EV benchmarks: Carla, ADAC's rule-of-thumb minimum, Generational, TÜV NORD/Carly and Arval.
Methods differ between sources (AVILOO calculates SoH itself; owner readings come from the car's own battery management system), so treat differences of 1–2 points as noise. Sources: every data point is listed with its date on the model pages and in the full source list; data download on open data.
Get this specific car tested
Ad disclosure: we are not currently paid by these providers. If that changes, the specific links will be marked "(paid link)" and this box labelled "Ad". How we make money.
Model averages can't tell you about the car in front of you. An independent battery test (typically a short OBD plug-in test, some remote) gives an SoH figure and often a certificate you can use when negotiating.
- AVILOO – Independent OBD-based battery test (FLASH / Premium) with certificate; available via partners in the UK and EU.
- Generational – UK OBD plug-in test with certificate (SoH, range, remaining warranty, cell balance); sold through dealers and independent mobile testers.
- Moba – Postal OBD kit: you run the test yourself and post the box back for a digital battery certificate (Europe – check vehicle support and delivery country).
Prices change – check the provider's site. Provider names are used for identification only.
FAQ
How accurate is this battery health estimate?
It shows what published data says is typical for the model at that mileage, not the condition of a specific car. In AVILOO's 2026 report, cars of the same model at similar mileage differed by up to 13.5 percentage points, so only a battery test of the car itself tells you its real state of health.
Where do the numbers come from?
From the 310 sourced data points on our model pages (independent test datasets such as AVILOO, dealer and fleet data, single-car tests and owner-reported readings) plus all-EV benchmarks from Generational, Carla, ADAC, TÜV NORD/Carly and Arval. Each result lists the datasets used, their sample size and a link to the source.
Is my input stored?
No. The estimator runs in your browser; nothing you enter is sent to us or stored, and no cookies are set.
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