Monitor Test
It fills the screen with a solid color so you can check for stuck dots (dead pixels), blotches, and burn-in. Press a color button to start the full-screen test.
Press a color button and the whole screen fills with that color. Look closely for stuck dots or blotches.
How to use
- Check for dead pixels and brightness blotches in the solid-color steps.
- Use the grayscale and gradient steps to check for banding or color shifts.
- Use the checkerboard and response steps to inspect ghosting and screen transitions.
- Click/tap or use the arrow keys to move between steps; press Esc or End test to finish.
Frequently asked questions
How do I find dead pixels?
Switch between white, black, and red, green, blue screens, and look for any dot that stays always on or off unlike its surroundings.
Can it check burn-in too?
If a faint afterimage of a previous screen shows on a solid (especially gray or white) screen, it may be burn-in.
Does it work on smartphones?
Yes. It works full-screen in mobile browsers too, and tapping the screen moves to the next color.
Can this test verify color accuracy?
No. Browser and operating-system color management and panel settings can change the display, so this does not replace professional color measurement.
Practical example and verification criteria
Monitor Test: First distinguish whether you need calculation, recording, timing, audio, or a screen check, then set units, intervals, repetitions, volume, and storage options for the real environment. Locally saved data may exist only in the current browser and device and can disappear when browser data is cleared, private mode is used, or the device changes.
Monitor Test: For a quick check, start with #000000 / #FFFFFF / RGB as a small input whose result relationship you can verify directly. Confirm that the input summary, units, and options match your intent before applying the tool to real values or a copy of the source; this reduces setup mistakes.
Monitor Test: Before relying on a timer or alert, test sound, volume, screen lock, and background behavior over a short interval, and also register important schedules in an operating-system alarm. Reopen exported files to verify saved results. Audio and screen results depend on hearing, ambient light, and device settings and do not replace professional measurement or long-term storage.
Monitor Test · Work record: For real work, record the input conditions, selected options, and result together. Do not assume the same state will remain after a refresh or device change. Preserve important results separately using copy, download, a screenshot, or another method the page supports, then reopen them in the target environment.
Monitor Test · Error check: If an error or unexpected result appears, reduce the input, run again with default options, and then change one condition at a time. Recording error messages and boundary values helps distinguish format issues, unsupported cases, and browser resource limits, and prevents an empty result from being mistaken for success.
Monitor Test · Scope of use: Check the page guidance for browser processing versus server lookup, storage location, and supported scope. Use sensitive source material or secrets only when strictly necessary. High-impact work such as legal, financial, or medical decisions or changes to an operational system requires current authoritative information and a separate verification process.