Short answer: Open a solid-color page, enter fullscreen at native resolution, and inspect the entire surface systematically. White and black first, then RGB, takes about five minutes on any modern browser.
Fullscreen color testing is the low-tech method repair techs still use — because it works on every panel type without calibration hardware.
When it is worth your time
- New hardware: First week with a monitor, laptop, tablet, or phone
- Return windows: Document defects before policies expire
- Mystery spots: Flicker, tint, or dots that appear on some backgrounds only
- Creative work: Quick sanity check before color-critical editing
- Cleaning prep: See every smudge before you wipe (cleaning guide)
Setup checklist (60 seconds)
- Close overlays — chat apps, notifications, and browser extensions can block pixels.
- Zoom 100% in the browser; OS scaling is fine, but browser zoom is not.
- Use native resolution where possible.
- Dim the room for black and grey tests.
- Click fullscreen on the tool page — partial coverage misses edge defects.
Suggested color sequence
| Step | Color | Goal |
|---|---|---|
| 1 | White | Dead pixels |
| 2 | Black | Stuck / hot pixels |
| 3 | Red, green, blue | Sub-pixel channel faults |
| 4 | Grey | Uniformity and banding |
Detailed breakdown: best colors for dead pixel tests.
TestMyGears tools at a glance
| Job | Where to go |
|---|---|
| Solid color backgrounds | All screen colors |
| Auto color cycling | Display tests |
| Touch coverage and accuracy | Touch screen test |
| Key rollover check | Keyboard test |
Desktop vs phone
Phones and tablets: Test portrait and landscape. Edge touch and brightness issues sometimes appear in only one orientation.
Desktops: If you use dual monitors, run the test on each display separately. Fullscreen applies to one screen at a time.
Fullscreen shortcuts
- Windows / Linux: F11 or the on-page fullscreen control
- macOS: Green window button or the tool’s fullscreen button
- Mobile: Browser fullscreen; add to home screen for quicker access next time
Press Esc to exit when finished.
Errors that waste your time
- Testing in bright sunlight
- Skipping RGB after white/black
- Staring only at the center (laptop corners matter)
- Calling a speck “dead” before cleaning — see dead pixel test guide