Hardware · 2026-04-14
Controller battery life
The Gamepad API rarely exposes a trustworthy battery percentage. A slot that drops after an hour may be charge, sleep, or radio.
What to check first
If the browser offers a battery level, the tester shows it. If it shows a dash, that is an API limit, not a dead cell. DualSense and Xbox Series pads commonly last a day’s play on a charge. Joy-Con and older pads vary more. Charge fully, retest on USB, and only then suspect the cell. Opening a lithium battery pack is a repair-shop job.
- USB play removes the battery from the question.
- Bluetooth drops plus a stable USB test point at the radio or the charge.
- Do not puncture the pack to “see the cells.”
Confirm the reading on the live tester before you buy parts or change firmware. The number on that page is what your browser actually receives.
A practical next step
Repeat the same test after each change and write the resting radius down. A fix that does not move that number did not fix the sensor. If the offset stays above about 0.12 with your hands off the sticks, plan a module replacement rather than another software pass. Model notes live in the controller library.
Frequently asked questions
Does this page change my controller?
No. GamepadTesters only reads the Gamepad API in your browser. Calibration writes, firmware updates, and stick swaps happen in the maker’s tool or at a repair bench.