Monitor & Display Test Patterns
These patterns each isolate one panel behaviour. Run them in a dim room, at 100% browser zoom, with any "night light" or colour filter turned off — otherwise you are testing your software, not your screen.
- 8 test patterns
- Dead & stuck pixels
- OLED, IPS, VA
- Runs in-browser
Running the patterns in a sensible order
- Start with the checkerboard — it finds hard pixel faults fastest.
- Then gray uniformity for backlight problems across the whole panel.
- Then gradient for bit-depth and banding.
- Then pixel response for motion behaviour.
- Finish with viewing angle and colour accuracy, which are judgement calls rather than pass/fail.
Reading the results honestly
Most panels fail something. A little corner glow on IPS, faint banding on an 8-bit panel, and slight tint shift off-axis are normal manufacturing variance, not defects. What warrants a return is a fault you can see during ordinary use from a normal viewing distance — most manufacturer warranties state a dead-pixel count threshold, so check yours before you file a claim.
Screen Tests — common questions
How long should an OLED burn-in test run?
At least 30 seconds per colour. Burn-in shows as a faint ghost of previously displayed content and is easiest to see on solid mid-grey and solid colour fills.
Is banding on a gradient always a fault?
No. Many laptop and budget monitor panels are 6-bit plus dithering, so mild banding is expected. Hard, wide steps that do not shimmer are more likely a driver or colour-profile issue.
Can a browser measure my monitor's accuracy?
No. A browser can only display patterns. Measuring gamma, white point or Delta E requires a hardware colorimeter.
Related sections
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Fill your monitor, TV or phone with one solid color. Useful for spotting dead pixels, dust, backlight bleed and uneven panels.
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Every display tool, one click away
All 34 tools in this section, grouped by what they do. Back to the Display Tools hub.