Full screen colour — white, black and every shade between
A plain sheet of colour that fills the whole display. Use it to hunt dead pixels, to see the dust you are wiping off, as a soft fill light for a product photo, or as a chroma key backdrop. Pick a colour, press F, and the browser gets out of the way.
- No signup, no watermark, nothing saved
- Works offline
Full intensity — #FFFFFF. This is what you want for pixel testing.
2.1 megapixels of one colour. The file is written straight into a compressed stream rather than painted onto a canvas, so even 8K stays small and will not exhaust a phone. Exports use the colour as shown, so the intensity slider is baked in.
How it works
- 1
Pick a colour
White and black cover most jobs. The pure red, green and blue swatches drive one subpixel at a time, which is how a stuck pixel gives itself away. The hex box takes any colour you paste, so a brand colour or a specific chroma green is one field away.
- 2
Set the intensity
The slider dims the colour by scaling it toward black, which is not the same as turning your monitor down. Leave it at 100% for pixel testing — a dimmed white can hide a weak subpixel. Pull it down when the screen is being used as a light and full brightness is blowing out the shot.
- 3
Fill the screen
Press F, press Space, or click the colour. Everything else disappears — no toolbar, no address bar, no cursor after a moment. The on-screen hint fades away too, so on a green screen there is nothing left in frame but the green. ESC brings the page back.
- 4
Download it if you need it elsewhere
A PNG at any resolution up to 8K, or exact pixel dimensions you type in. Useful as a wallpaper, a blank slide, a backdrop layer in a video editor, or a test pattern for a projector or a second monitor that has no browser on it.
What people use a blank colour screen for
Finding dead and stuck pixels
A dead pixel stays black no matter what, so it only shows against a white or a bright field. A stuck pixel is the opposite problem — it is jammed on one colour, so it hides on white and glares on black. Cycle white, black, red, green and blue and watch the same patch of screen each time: a dot that stays dark on white is dead, a dot that stays lit on black is stuck, and a dot that vanishes on green but shows on red and blue is one subpixel that has failed. Get close enough to see individual pixels, because a fault three feet away looks like a speck of dust.
Cleaning a screen without smearing it
Dust and fingerprints are almost invisible on a page full of text and impossible to judge on a dark desktop. A white field shows dark specks and hair; a black field shows grease, smears and the streaks a dry cloth leaves behind. Clean with white on the screen, then switch to black to check your work — most people stop too early because the first pass looked clean on white. Turn the display off before using any liquid, and put it on the cloth rather than on the panel.
A fill light for product photos and video calls
A laptop or tablet showing a full white screen is a large, soft, even light source, which is exactly what small objects photograph well under. Placed off to one side it opens up the shadows a phone camera would otherwise crush to black; placed in front of you it does the same for your face on a call. The warm and cool white swatches shift the colour temperature so the light matches the room instead of fighting it, and the intensity slider is your dimmer. Screens are weak lights, so bring it close and keep the shutter slow or the ISO high.
Chroma key green and blue
Green screen software keys out one narrow band of colour, so an even, saturated, unbroken field is worth more than a bright one. A tablet propped behind a small object — a hand, a phone, a toy — makes a backdrop big enough for a close-up shot without a roll of fabric. Green is the usual choice because camera sensors carry the most detail in the green channel; blue is better for anything green in the frame, and for subjects with blonde hair, where green spills badly. Keep the subject well away from the panel so the colour does not reflect onto its edges.
Checking uniformity, backlight bleed and banding
A full black screen in a dark room is the standard test for backlight bleed: the pale glow creeping in from the corners of an LCD, and the faint cloudy patches sometimes called flashlighting. A full white screen shows the opposite fault — tinting, where one region of the panel runs warmer or cooler than the rest. The mid grey swatch is the one to use for banding, where a panel that cannot resolve enough steps shows visible bands instead of an even tone.
A blank backdrop for sharing a screen
A plain colour makes a clean background to draw on with a stylus, a neutral surface behind a physical object held up to a webcam, or a blank slide between two topics in a presentation. It also hides everything on your desktop instantly, which is worth knowing before you share your screen in a meeting.
Frequently asked questions
How do I tell a dead pixel from a stuck one?
Look at the same spot on a white screen and then on a black one. A dot that stays black on white is dead — that pixel receives no power and cannot be revived. A dot that stays coloured on black is stuck, meaning one or more subpixels are jammed on. Stuck pixels sometimes free themselves after the area is exercised by rapidly changing colours or gently massaged through a soft cloth; dead pixels do not come back. Either way, count them: most manufacturer warranties only replace a panel above a set number of faults, and the count is usually higher than people expect.
Does this actually clean my screen?
No — it only makes the dirt visible. Nothing a web page does can move dust. What the white field gives you is contrast: specks, hairs and fingerprints that vanish against a normal desktop stand out against a flat colour, and the black field catches the greasy smears that white hides. Switch between the two while you wipe and you will stop while the screen is actually clean instead of when it merely looks clean.
Why does white look grey or yellow on my screen?
Almost always something else on the device is adjusting the picture. Night Shift, Night Light and blue-light filters warm the whole display towards orange after dark. True Tone and adaptive brightness change the white point to match the room. Ambient light sensors dim the panel in a dark room. Turn those off before judging a panel, and compare with a sheet of white paper under the same light — the paper is a fairer reference than your memory of what white looks like.
Which green should I use for a chroma key?
The broadcast standard is roughly #00B140, the shade sold as chroma key green, and it is the preset labelled that way here. Pure #00FF00 is more saturated than any camera can record cleanly and tends to bloom and spill onto the subject. Whichever you choose, an even field matters more than the exact hue: keep the panel out of direct light so it does not develop a bright patch, and keep the subject far enough forward that green light is not bouncing off their shoulders.
Does fullscreen work on an iPhone?
Not the real thing. Safari on iPhone does not let a web page put an ordinary element into fullscreen — only video gets that privilege — so the fullscreen button would silently do nothing. This page detects that and covers the entire viewport instead, which hides the page, the tab bar and everything else; Safari keeps a thin address bar unless you scroll it away. On iPad, Mac, Windows and Android the Fullscreen API is available and you get a genuinely edge-to-edge colour. Fullscreen also needs a tap or a keypress to start, which is a browser rule, not a choice made here.
Will my screen dim or sleep while it is showing?
The page asks the browser to hold a screen wake lock while the colour is filling the screen, which keeps most modern browsers from dimming or sleeping the display. It is released the moment you exit. Some browsers do not support it and some refuse it on battery power, so if you are using the screen as a light for a long shoot it is worth turning the device sleep timer up as well.
What is the brightness slider actually doing?
It scales the colour toward black — at 50% a pure white becomes a mid grey. Your monitor stays at whatever brightness you set it to. That distinction matters for testing: a dimmed white is a grey field, and a grey field can hide a weak subpixel that a true full-intensity white would reveal. For pixel hunting leave it at 100% and use the display’s own brightness control. For lighting a photo the slider is the more convenient dimmer of the two.
Why would I download a PNG instead of just using the page?
Because plenty of screens have no browser on them. A solid colour image can be set as a wallpaper, loaded from a USB stick into a TV or a projector, dropped into a video editor as a backdrop layer, used as a blank slide, or sent to a device that only opens images. The exported file is a plain PNG with no watermark and no metadata beyond the pixels.
Is an 8K PNG going to be a huge download?
No. An 8K frame is 33 million pixels, but every one of them is identical, and PNG compression is very good at that — the file usually lands in the low hundreds of kilobytes. It is also built without ever drawing those pixels: the image is written row by row straight into a compressed stream, so a phone can export an 8K file without the memory spike that painting a 33 megapixel canvas would cause. On a browser too old for that method the largest sizes are turned off rather than left there to crash the tab.
Is anything I do here sent anywhere?
No. The colour, the intensity and the exported PNG are all produced by your own browser; nothing you choose is transmitted or stored, and the tool keeps working with the network switched off. Like every page on this site it does carry advertising, and those ad requests are made by the ad network as usual — but they receive nothing about what you are doing with the tool.