A FULLSCREEN UTILITY · FREE FOREVER · NOTHING TO INSTALL
PURE BLACK SCREEN
The fastest way to make any display completely black. Test for dead pixels, save battery on OLED screens, spot dust while you clean, or give your monitor — and your eyes — a rest.
Works on PC, tablet & phone · Nothing leaves your device · No ads
Or press F · 1–6 switches color · click the panel too
On iPhone, the color fills the browser window — iOS limits true fullscreen.
01 — Use Cases
Why people go black.
Dead & stuck pixel tests
Solid full-screen colors make faulty sub-pixels impossible to miss. One dot that never changes is all it takes.
OLED battery saving
On OLED panels, black pixels switch off entirely. A black screen is the closest thing to sleep your display can do while staying on.
Screen cleaning
Bright, even colors turn every speck of dust, fingerprint and smudge into high-contrast evidence. Wipe with confidence.
Monitor rest
Blackout the screen between tasks instead of leaving a glowing desktop burning into the panel for hours.
Light-sensitive rooms
Bedrooms, nurseries, darkrooms and astrophotography setups. Kill the glow without reaching for the power button.
Presentations & projection
Go black between slides without touching the projector — the room stays dark, the meeting keeps moving.
02 — The Palette
Every color, full screen.
Black is the headline act — but every solid color has a job to do. Click any band to open it fullscreen.
03 — The Test
The sixty-second dead pixel test.
Four steps, one minute, a verdict. Your screen either passes — or you've just met your first dead pixel.
Auto-cycles black → white → red → green → blue, about two seconds each. Tap or press Esc to stop.
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Clean first
Wipe the screen gently with a dry microfiber cloth. Half of all "dead pixels" turn out to be dust.
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Run the test
Press Start and let the screen cycle black, white, red, green and blue at full size. Stand back a little — arm's length is ideal.
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Watch each color
Give every color three to five seconds. A dead pixel stays black on all of them. A stuck pixel glows on some but not others.
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Check your warranty
Note the locations, then read your manufacturer's policy — most require a minimum defect count before they replace a panel.
- Dead pixel
- Black dot on every color. The sub-pixel receives no power at all.
- Stuck pixel
- Fixed single color — often red, green or blue. The sub-pixel is locked on one signal.
- Dust
- Moves when you wipe. Always clean before you judge.
Know your enemy
04 — The Science
True black, zero light.
The two panels below are real pixels on your screen, side by side. If you look closely — or dim the lights — the left one is lighter. That glow is your backlight.
Typical LCD / LED panel
Backlit
OLED panel
Self-lit
Less display power draw, measured in laboratory tests, for dark interfaces at high brightness on OLED panels. A pure black screen is the darkest interface there is.
That's why this tool exists: on an OLED phone or TV, black pixels are switched-off pixels — the screen rests, the battery rests, and the room goes properly dark. On an LCD, the same black screen still hides your content, but the backlight keeps burning behind it.
05 — Questions
Straight answers.
Testing displays for dead or stuck pixels, saving battery on OLED screens, spotting dust and smudges while cleaning, resting a monitor without shutting it down, and killing stray light in bedrooms, darkrooms and photography setups.
On OLED and AMOLED displays, yes — every black pixel switches off completely, so a full black screen draws almost no display power. On LCD screens the effect is minimal, because the backlight stays on behind the black image.
Clean the screen first with a dry microfiber cloth, then run the pixel test. The screen cycles through fullscreen black, white, red, green and blue. A dead pixel stays black on every color; a stuck pixel shows the wrong color on some. Note the locations and check your warranty terms.
Yes. Tap any swatch or the preview panel to fill the screen. On iPhone, Safari limits true fullscreen for websites, so the color fills the browser viewport instead — still completely black.
Completely free. No downloads, no accounts, no ads — and once the page has loaded it keeps working even offline.
On LCD monitors a glowing backlight sits behind the image, so black is really a very dark gray. OLED panels light each pixel individually, so black means the pixel is switched off — true #000000.