Language: EN

Night Clock

Turn an old phone or tablet into a bedside clock. Big digits on pure black, in red, amber, gray or white, down to a very low brightness. The clock moves a little every minute to protect the screen from burn-in, and it can dim itself further at night. No alarm, no sound.

Click the clock or press F for full screen. Press Esc to exit.

Color

Style

Hours

How to use it

  1. Pick a color and turn the brightness down until the digits are just readable from your pillow.
  2. Choose a style (thin, bold or digital), 12 or 24 hour time, and whether to show seconds or the date.
  3. Click the clock or press F for full screen. The up and down arrows change the brightness.
  4. To leave, press Esc, or tap the screen and use the dim Exit button in the bottom right corner. A tap on the clock does not exit, so you will not light up the room by accident.

Also turn your device's own brightness to the lowest setting and plug it in. The page keeps the screen awake while it is full screen, in browsers that support it.

Set up an old phone or tablet as a bedside clock

  • Add it to the home screen. On iPhone and iPad tap Share, then Add to Home Screen; on Android use the browser menu. It then opens full screen without the address bar.
  • Turn on Do Not Disturb so notifications do not light up the screen at night.
  • Use a stand and plug in the charger. A clock that stays on all night needs power.
  • Pick red or amber. Red lights only the red part of each pixel, so at the same setting it gives off less light than white. Amber is a little brighter and easier to read.
  • Dim more at night. Set the hours, for example 10 PM to 7 AM, and how dim to go. The clock changes brightness gently at those times.

Burn-in protection, honestly

OLED screens make light in each pixel, and pixels that show the same bright image for many hours age faster than the rest. Over months that can leave a faint ghost of the image, called burn-in. A clock is a classic case: the same digits in the same place every night.

This page reduces the risk in three ways:

  • Pixel shift. Every minute the whole clock glides to a new random spot on the screen, so the wear is spread over a wider area instead of the same few pixels.
  • Low brightness. Dimmer pixels age more slowly. The night dimming lowers it further while you sleep.
  • Pure black background. On OLED the black pixels are off and do not age.

This lowers the wear; it does not make it zero. LCD screens do not burn in the same way, though they can briefly hold a faint image that fades.

Questions

Does the night clock have an alarm?

No. It is a clock only: no alarm and no sound. Use your phone's own alarm app, which works even when the screen is locked.

What is the best color for a bedside clock?

Red or amber at a low brightness gives off the least light while staying readable. Red lights only the red subpixels, so it is the dimmest at the same setting. Gray and white are easier to read but brighter.

Will the screen stay on all night?

While the clock is full screen, the page asks the browser to keep the screen awake. Most current browsers allow it. If yours does not, set the device's auto-lock to Never and plug it in.

Is this an OLED clock?

It works on any screen, and it is built with OLED in mind: a pure black background with the pixels off, low brightness and a clock that moves every minute to spread the wear.

Why does the clock move?

That is the burn-in protection. The clock moves to a new spot once a minute. You can turn it off, but on an OLED screen that is left on every night it is better to keep it on.