Red Screen
A solid, bright red screen (#FF0000). Go full screen for a red light, or lower the brightness for a dim glow.
Uses for a red screen
Protect your night vision
Dim red light affects dark-adapted eyes less than white light. Stargazers and campers use it to read maps and notes at night.
Red light for photos and video
Point a red screen at your subject for a strong red glow in selfies, music videos and short clips.
Red subpixel test
A full red screen lights only the red subpixels. A dot that stays black or shows another color is a faulty pixel.
Warning or cue screen
Use a red screen as a stage cue, a wrong-answer signal in a quiz or an alarm effect in an escape room.
Mood lighting
At low brightness, a red screen gives a warm, dim light for parties or relaxing.
Bright red or dark red
At full brightness the screen is pure red. Move the brightness slider down for a deep, dark red light that is easier on the eyes at night.
How to use it
Press Full screen, click the colored area or press F on your keyboard. Adjust the brightness slider if the screen is too bright. Press Esc, or tap Exit on a phone, to return to the page.
Frequently asked questions
Is red light better at night?
Many people find dim red light easier on dark-adapted eyes than white or blue light. Keep the brightness low for the best result.
Which red does this screen use?
Pure red, #FF0000, the brightest red your display can show. The brightness slider darkens it without changing the hue.
Is it free? Do I need to install anything?
Yes, it is free. Every screen runs in your web browser on a computer, phone or tablet. There is nothing to download and no account to create.
Do you store or upload anything?
No. Your settings are saved only in your own browser so they are ready next time. We do not use cookies, and we count visits with cookieless analytics.