About Dead Pixel Test Online.
We build minimalist, performance-driven web tools to diagnose screen health. Simple, accurate, and completely private.
Our Mission
Displays are our primary interface to the digital world. Whether you are editing photos, gaming at high frame rates, or reading text, a single defective pixel can disrupt your workflow and viewing experience.
Our mission is to provide an instant, high-fidelity, distraction-free environment to inspect displays of any size—from desktop monitors to mobile phones—without requiring software installations, sign-ups, or invasive ads.
How it was built
Dead Pixel Test Online was designed with simplicity and efficiency in mind. Built using modern, lightweight client-side scripts, the testing canvas renders solid color screens directly in your browser.
By utilizing native web APIs (like full-screen display APIs and viewport coordinates registry), our tool provides the utility of heavy native desktop testing programs in a single lightweight web page.
Why use our tool?
100% Privacy First
All coordinates marked and calculations done remain strictly in your browser. We never collect or upload your screen activity or results.
Multi-Device Ready
Responsive viewport calculations make testing seamless on 4K desktop monitors, ultra-wide displays, laptops, iPhones, and Android units.
Interactive Reporting
Tap the display during testing to pinpoint stuck or dead pixel coordinates, and export a diagnostic report in PDF, CSV, or JSON.
Understanding Pixel Defects
Modern liquid-crystal (LCD) and organic light-emitting diode (OLED) displays consist of millions of sub-pixels. Defects typically fall into three categories:
Dead Pixel
A dead pixel is caused by a transistor that receives no power, resulting in a pixel that remains permanently black. They are most visible on bright, solid backgrounds.
Stuck Pixel
A stuck pixel occurs when one or more sub-pixels (red, green, or blue) stay continuously illuminated. They display a persistent bright color on black or contrasting backgrounds.
Hot Pixel
A hot pixel is a pixel whose sub-pixel elements are stuck fully ON, glowing bright white across all background colors.
Ready to test your screen?
Run our fullscreen diagnostic test now to identify display defects.