Battery Test
Read browser-reported battery level and charging status, record observations over time, and export them.
Test interface
Your browser may ask for permission after you press Start.| Time | Level (%) | Charging |
|---|---|---|
| — | ||
How to use this tool
- Click Check battery to request the Battery Status API where supported.
- Read the reported level and charging state.
- Start a timed observation to record changes, then stop it.
- Export the observations as CSV or JSON if you want to keep them.
Advertisement
Technical explanation
The Battery Status API exposes level and charging state in browsers that still implement it. It provides an estimate, not a measurement of capacity or health. Many browsers have removed or restricted the API for privacy reasons.
A battery level that drops quickly may reflect workload, temperature, or calibration. This page cannot read cycle count, design capacity, or manufacturer health data.
Troubleshooting
Battery information is unavailable
Your browser may not support the API. This is a browser limitation, not necessarily a battery fault.
Level does not change
Level is reported in coarse steps and may update slowly. Use the timed observation over a longer period.
Values differ from system settings
Browser reporting and operating-system estimates can differ.
Export does nothing
Allow downloads for this site and try a different browser if the Blob download is blocked.
Related tools
Frequently asked questions
Advertisement