One tap fills your display with white or any colour. Set brightness, warmth and an auto-exit timer. No flashing.
A full black screen has a few different jobs. On a monitor or phone it shows stuck pixels, the bright dots that stay lit when everything around them is dark, so turn the room lights down and look from close up. On an OLED panel, black means the pixels are switched off, so you can see whether the screen glows evenly or leaks light at the edges. Some people open it as a plain dark backdrop for a video call, a projector test, or to hide a bright desktop while others watch a presentation. This page opens with the black colour already chosen, so you only press Go full screen. The brightness slider has no visible effect on black, and the warmth slider only applies to white. Use the number keys to switch to other colours without leaving. One honest limit: a black screen on an LCD still shows some backlight, so a dark gray glow around the edges is normal and not a fault. Tap or press Esc to leave.
A white screen fills your whole display with one plain colour, and this page does it in a single tap: press Go full screen and the browser hides its toolbars. People use it as a soft lamp for reading in a dark room, as fill light for a video call or a photo, to check a monitor for stains and dust, to see dead pixels, and to clean a screen so every smudge shows. Held close to a subject, a bright white phone or laptop screen lights a face much more evenly than a bare room bulb. A sheet of tracing paper or thin white cloth over the glass softens it further for a makeshift light box. The colour chips cover white, black, red, green, blue, yellow, orange, pink, purple and gray, and the Custom chip takes any hex code such as #ffcc00.
The brightness slider runs from 10 to 100 percent and dims the colour painted on the page. It is separate from your device brightness, which you still set with the system controls, so for the brightest light turn both up. The warmth slider appears for white. Moving it to the warm side lowers blue, which gives a softer, yellower light that is easier on the eyes at night. Moving it to the cool side lowers red for a bluer tone. This is a simple red and blue balance, not a measured colour temperature in kelvin. While the colour is up, the page asks the browser to keep the screen awake using the Screen Wake Lock feature. Many current browsers support it. Where it is missing, your phone may still dim or lock after its normal timeout, and you will need to change the device setting.
Tap or click anywhere to leave. Press Esc to leave from a keyboard. While the colour is up, keys 1 to 9 and 0 switch between the ten colour chips without leaving. The optional Close after timer ends the screen by itself after 1, 5, 10, 30 or 60 minutes, which suits a night light you do not want to leave on. A short hint shows at the start and while the timer runs, then fades so the screen stays plain. The cursor is hidden in full screen. The page never flashes or alternates colours on its own, because rapid flashing can trigger seizures in people with photosensitive epilepsy. Every colour is steady until you change it.
Browsers on iPhone often do not allow full screen for a page element. In that case the colour fills the page instead, covering the content, and you still leave with a tap. The address bar may remain visible there. A white screen is a weak light source next to a real lamp, it can leave a faint afterimage on some screens, and very long use of a bright screen drains the battery and, on OLED panels, can contribute to image retention. The colours are drawn by your browser, so they are only as exact as its colour settings, night mode and filters. Your chosen colour, brightness, warmth and timer are saved in this browser so they are there next time. Nothing is uploaded, and the page counts visits with Google Analytics, never what you chose.
On an LCD monitor the backlight is always on, so black shows as a very dark gray, brighter at the edges in a dim room. On an OLED screen the pixels switch off and black looks truly black.
Dim the room, go full screen, and look from about 20 cm. A stuck pixel is a small bright dot of one colour that stays lit. Then try red, green, blue and white, because some defects show on only one.
Press Go full screen on this page. The white fills the display and the browser bars hide. Tap anywhere or press Esc to leave. If your browser blocks full screen, the white fills the page instead.
Yes, as a soft light for a short distance. At full brightness it can light a face for a video call or a book held 30 to 60 cm away. It is far weaker than a lamp, so use it for close work, and add some warmth for evening use.
The page requests a screen wake lock while the colour is up, which works on many current browsers. If yours does not support it, raise the Auto-lock or Screen timeout setting in your phone, for example to 5 minutes, before you start.
No. Each colour stays steady until you change it with the chips or the number keys. There is no strobe or flicker mode, because rapid flashing can trigger seizures in people with photosensitive epilepsy.
Choose 1, 5, 10, 30 or 60 minutes under Close after, then press Go full screen. When the time is up the colour closes by itself. Leave it on Off to stay until you tap or press Esc.
Safari on iPhone usually does not let a page element go full screen. The page then fills the browser window instead, which still hides the content. For a true full screen, use a laptop, an Android phone or a tablet.