Check if your monitor uses PWM backlight dimming — a common cause of eye strain and headaches

60 Hz
Selected test frequency
Preview — click "Start Flicker Test" for fullscreen
How to test:
  1. Set your monitor to 50–75% brightness (PWM is inactive at 100%).
  2. Select a frequency above and click "Start Flicker Test".
  3. Open your phone's camera app and point it at the screen.
  4. Look for horizontal dark bands moving across the camera image.
  5. If you see bands, tap "I See Banding" below. If not, tap "No Banding".

This test runs entirely in your browser. No data is collected or transmitted.

⌨ Free PWM Flicker Test by KeyboardTester.click