No download · Pure red · 100% free

Red Screen Test Online for Dead Pixel Check

Free online red screen test to check for dead pixels, red sub-pixel defects, and color uniformity on OLED, LCD, and phone displays. Pure red fullscreen — no install needed.

Click for Fullscreen Red Screen

Best for spotting pixel defects

Dead Pixel Finder

A pure red screen reveals dead pixels as tiny dark or black dots where the red sub-pixel fails to activate.

Red Sub-Pixel Test

Test the red sub-pixels independently to isolate defects specific to the red color channel on any display.

Color Uniformity Check

Verify that the red color appears evenly across your entire display without patches or color variations.

All Devices Supported

Works on OLED TVs, gaming monitors, laptops, tablets, and smartphones — iOS and Android.

Why Use a Red Screen Test for Dead Pixel Detection?

A red screen test isolates the red sub-pixels on your display, making it easy to detect dead pixels and color-specific defects that might not be visible on other test patterns.

Dead pixels appear as tiny black dots on the red screen — red sub-pixels fail to light up.
Stuck pixels show as green, blue, or white dots against the red background.
Red color uniformity issues reveal manufacturing defects and panel aging.
Fullscreen mode provides the most accurate results for spotting individual pixel defects.

What This Red Screen Test Reveals

Each issue becomes visible on a pure red background

Dead Red Sub-Pixels
Stuck Pixels (Wrong Color)
Red Uniformity Issues
OLED Red Pixel Aging
Color Channel Defects
Panel Manufacturing Defects

Complete Guide to Red Screen Test & Red Sub-Pixel Dead Pixel Check

A pure red screen isolates the red sub-pixel channel, making it the most effective test for red-specific pixel defects on any display type.

This free online red screen test fills your entire display with pure red (RGB 255, 0, 0) so you can perform a red sub-pixel check, detect dead pixels, and spot color uniformity issues on OLED, LCD, and AMOLED screens — no software installation required.

How to Perform a Red Screen Test for Dead Pixel Detection

Follow these steps to use our free red screen test for the most accurate results:

  1. Set your display brightness to at least 50% for optimal defect visibility.
  2. Click "Enter Fullscreen Red Screen" above to fill your entire display with pure red.
  3. Look carefully for any black dots on the red screen — these indicate dead red sub-pixels.
  4. Check for any pixels showing green, blue, or other colors — these are stuck pixels.
  5. Take a photo of any defects you find for warranty claims or return requests.

Detecting Dead Red Sub-Pixels with a Red Screen Test

Each pixel on your display consists of three sub-pixels: red, green, and blue. A red screen test activates only the red sub-pixels. Dead red sub-pixels appear as tiny black dots on the red background because they fail to produce red light. This test is more targeted than a white screen test because it isolates the red channel specifically.

Red Color Uniformity Test for OLED and LCD Displays

Color uniformity issues appear as patches of different red shades across your screen. On a perfect display, the red should appear identical everywhere. Our red screen test reveals manufacturing defects, panel aging, and OLED pixel degradation that affect the red color channel specifically.

OLED Burn-in Detection with Red Screen

OLED burn-in often affects individual color channels differently. A red screen test can reveal burn-in patterns from static red-heavy content like channel logos, game health bars, or notification badges. If you see faint ghost images or uneven red areas, your OLED display may have burn-in affecting the red sub-pixels.

Important: Combine with Other Color Tests

For a complete pixel test, combine the red screen test with green, blue, and white screen tests. Some pixel defects only appear on specific color channels. A pixel might work fine on green but fail on red. Testing all primary colors ensures comprehensive coverage of your display's health.

Supported Display Types for Red Screen Testing

This red screen test works on all major display technologies and devices:

OLED / QD-OLED / AMOLED

Individual red sub-pixels can be tested for degradation. Check for burn-in marks from red-heavy static content.

LCD / IPS / VA

Red sub-pixel defects are common on LCD panels. Test for dead or stuck red sub-pixels on any LCD monitor.

Phones & Tablets

Test smartphone or tablet screens for red pixel defects and color accuracy on any mobile device.

This free red screen test runs entirely in your browser with no download or sign-up required. Combine it with our other color tests for comprehensive display diagnostics.

Free Red Screen Test Online - Dead Pixel & Sub-Pixel Checker | OLED Burn-in Test