Symptoms
- Estimated range drops much faster than miles/km actually driven
- Estimate says one number but you run out sooner than expected
- Inaccuracy is worse on the highway or in extreme weather
- Estimate was more accurate when the car was newer
Likely causes
- CommonEstimate based on optimistic average conditionsRange estimates are often based on mixed or moderate driving and don't fully account for highway speeds, hills, or cold weather.
- CommonHighway driving at higher speedsEVs are generally less efficient at higher, sustained highway speeds compared to the conditions used for range estimates.
- CommonCold or hot weather increasing energy useClimate control and battery conditioning both use energy that estimates may not fully reflect.
- PossibleGradual battery degradation not yet reflected in the estimate baselineAs the battery ages, the estimate should adjust, but there can be a lag or inconsistency.
What to do
- Watch the percentage-based battery level alongside the mile/km estimate, since percentage is often more reliable for planning than the projected range number.
- Expect noticeably reduced real-world range at sustained highway speeds compared to city or mixed driving.
- Account for 20–30% less range in very cold or very hot weather when planning trips.
- Use trip-planning tools in the car's navigation or a manufacturer app, which often account for terrain, weather, and charging stops more accurately than the simple range number.
- Track your own real-world efficiency (miles or km per percentage of battery) over a few weeks to build a more personalized estimate.
- If the discrepancy is dramatic even accounting for these factors, have the battery capacity checked.
When to call a pro
If range is dramatically below the estimate even in mild weather and moderate driving, have a dealer check the battery's actual capacity.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.