Full screen colour test
Fill your screen with any colour you like, step through the standard test fields, or run them as a slideshow.
Esc to exit · arrow keys to change · H hides the controls
Dimming changes what is sent to the panel, so this is no longer an exact colour value. Return the slider to 100% before judging anything.
How to run this test
- Pick a colour from the presets, or type any hex value into the field and press Apply.
- Press Go full screen. Use the left and right arrow keys to step through the presets without leaving full screen.
- Press the space bar to start and stop the slideshow, H to hide the controls, and Esc to come back.
- Use the dim slider only for comfort. Return it to 100 per cent before judging anything, because dimming changes what is sent to the panel.
- Download any colour as a PNG if you want it as a wallpaper or a reference file.
What a problem looks like
- Dots that persist across every colour
- A pixel fault rather than dirt or a content artefact. Step through white, black and the primaries to work out which sub-pixel is involved, or use the nine-field sequence on the dead pixel test.
- Visible steps in what should be a flat field
- A flat colour showing bands or blotches points at the panel or at how the signal is being handled, not at the page. A solid field is a single value, so anything you see in it came from the display chain.
- The colour looks wrong compared with another device
- Usually a colour profile or a wide-gamut display rendering sRGB values without colour management. Compare the same hex value on two screens side by side before concluding a panel is at fault.
What to do next
If something looks wrong, check it again in a normally lit room and from straight on, then check whether it appears on a second device. If it only happens on this screen and you are still inside the return window, that is the time to contact the retailer.
Questions people actually ask
Can I use any colour, or only the presets?
Any colour. Type a hex value such as #1a2b3c into the field, or use the native colour picker next to it. Three-digit shorthand like #abc works too, and the field tells you if it cannot read what you typed.
Does the downloaded PNG match what I see?
The file contains exactly the hex value you chose, at the size you picked. What any given screen then does with that file is a separate question, which is the whole point of the test.
Why does the dim slider warn me?
Because dimming applies a brightness filter to the field, so the panel is no longer receiving the exact value you asked for. That is fine for comfort during a long session and useless for judging a fault, so the tool says which state it is in.
Is there a keyboard shortcut for the slideshow?
Yes. Once you are in full screen the space bar starts and stops it, the arrow keys step through colours manually, and H hides the controls so nothing overlays the field. Escape exits.