Battery Health Estimator

Work out your battery’s real health from its capacity figures.

What you provide

Result

PASS

Battery at 84% of its original capacity

Above 80% is considered healthy. Some wear is normal and expected; there is nothing to act on here.

Capacity remaining
0100
84.0%pass
  • Below 50% — significantly degraded
  • 50–80% — noticeable wear
  • Above 80% — healthy

Measured against the design capacity you entered, not against a new battery of the same model.

Diagnostic telemetry
Health
84.0%
Wear
16.0%
Design capacity
5000
Full-charge capacity
4200

What this cannot tell you

  • A browser cannot read your battery. These figures come from your own system report — this tool only does the arithmetic on what you supply.
  • Both capacities must be in the same unit (mAh or Wh). If they are swapped or mixed, the result is meaningless.
  • Capacity is one measure of health. A battery can also fail suddenly or swell, which no capacity figure predicts.

Take this with you

Battery Health Estimator on RunTheTests — free browser-based repair tools, no sign-up.