Dead Pixel & Stuck Pixel Test

Free online tool to find dead, stuck or hot pixels on monitors, laptop screens, phones, tablets and TVs. Choose a mode below — the test runs entirely in your browser, on a fullscreen solid-colour canvas. No data leaves your device.

Before you start
  • Clean the screen with a microfibre cloth — many "dead" pixels are actually dust.
  • Press F in the test to toggle fullscreen, or just click anywhere to dismiss any browser bars.
  • Keyboard: ← / → change colour, SPACE next, A auto-cycle, ESC exit.
  • On phones: tap to advance, swipe left/right to switch, double-tap to exit.
  • Run each colour for at least 30 s. Stuck pixels are easiest to see on solid black or white.

What's the difference between a dead pixel and a stuck pixel?

Modern LCD, OLED, IPS and AMOLED panels are built from millions of tiny picture elements ("pixels"), each composed of three sub-pixels: red, green and blue. When one of those sub-pixels — or all of them — fails to behave correctly, you get a defect that's visible against certain background colours.

Dead Pixel

A dead pixel stays black on every background — the cell receives no power and emits no light. It is most visible on white, red, green or blue backgrounds. Dead pixels are usually permanent and rarely recoverable, because the underlying transistor itself has failed.

Stuck Pixel

A stuck pixel is permanently lit in one colour (red, green, blue, or any combination). It is most visible on a black background. Because the transistor still works, stuck pixels can sometimes be recovered with the rapid RGB flashing technique used in our "Fix" mode.

Hot Pixel

A hot pixel is bright white at all times — typically a defect more common on camera sensors than displays, but high-density OLED panels can occasionally show them too. Treatment is similar to stuck pixels.

Sub-pixel Fault

Sometimes only one of the three RGB cells inside a pixel fails. The pixel will look normal on most colours but tinted on others. Our solid-colour cycle (red → green → blue) reveals these by making the bad sub-pixel stand out against its missing channel.

How to use this dead pixel test correctly

For the most reliable result:

  • Clean the screen first. Smudges and dust look identical to dead pixels under casual inspection. Use a soft microfibre cloth — never paper towels.
  • Reduce reflections. Dim the room or angle the screen so the displayed colour is what you actually see.
  • Run each colour for at least 30 seconds. Move slowly across the panel; defective pixels are often only a few millimetres wide.
  • Compare colours. A pixel that is invisible on red but visible on green points to a stuck red sub-pixel.
  • Use both bright and dark backgrounds. Dead pixels show on white, stuck pixels show on black.

Trying to fix a stuck pixel

The "Stuck-Pixel Fixer" mode rapidly flashes the affected area through the full RGB cycle. The constant electrical excitation can sometimes free a sub-pixel that has become trapped in a fixed state. Run the fixer over the affected region for 20–30 minutes; some stubborn pixels may need multiple sessions across several days.

Gentle physical pressure with a soft, clean cloth — applied to a powered-on screen showing the fixer animation — can also help. Never press hard: you can permanently damage the panel.

Warranty and acceptable defect counts

Manufacturers do not consider a single dead pixel grounds for return. The widely-used ISO 9241-307 standard defines four "classes" of pixel-defect tolerance, with most consumer panels shipping at Class II — typically allowing several dead/stuck pixels per million before a panel is considered defective. Premium "zero dead pixel" warranties are available from some manufacturers but usually require a separate purchase.

Always document your findings (a clear photo with the colour shown by this tool plus a coin for scale) before contacting support — most warranty teams require visual proof.

Privacy & security

This entire tool runs locally in your browser. No image, screenshot or test result leaves your device. There is no analytics, no tracking, and no server call required to perform the test. See our Privacy Policy.

Dead Pixel Test — FAQ

Quick answers to the most common questions about this tool.

What is a dead pixel?

A dead pixel is a permanently dark sub-pixel that no longer receives power. Stuck pixels, by contrast, are stuck on a single colour and can sometimes be revived.

How does the auto-cycle test work?

It fills the screen with pure red, green, blue, white, black and grey in turn — every 1.5 seconds. Any pixel that fails to follow is suspect.

Can this fix stuck pixels?

Sometimes. Rapid colour cycling for 10–60 minutes can free up a stuck transistor. Dead pixels (no power) cannot be fixed by software; they require a panel replacement.

Is this safe for OLED screens?

Short tests are fine. Avoid running pure-white or pure-blue stills for hours on OLED — that is what causes burn-in. The auto-cycle pattern explicitly rotates colours to prevent this.