Tool categories
Start below, switch to full screen, and inspect the entire panel on a clean black background.
Display diagnostic
Check dead, stuck, hot, and uniformity issues with solid colors, then optionally run a targeted pixel repair attempt.
Clean the screen first, open fullscreen, then scan the panel in slow rows. Use click, Space, or arrow keys to move between colors.
Screen Tester is a free, browser-based screen testing tool that lets you inspect monitors for backlight bleed, glow, and bright display defects.
A black screen test gives you a clean dark background for checking monitor defects that are easier to see when the panel should be almost completely dark. It is commonly used for backlight bleed, IPS glow, bright spots, and hot pixels.
If you need the opposite type of check, the full screen tester includes a white background for stuck pixels, tint, and uniformity inspection on bright screens.
Yes. Backlight bleed usually becomes much easier to notice on a dark screen in a dim room, especially around the corners and edges.
They help with different things. Black is useful for bright defects and bleed, while white and RGB screens are often better for confirming dead or stuck pixels.
Yes. Start the display test and switch into full-screen mode for a cleaner inspection surface.
Detect if your display runs at 60Hz, 144Hz, 240Hz or higher
Check color accuracy, gradient banding and backlight uniformity
Check your LCD monitor for backlight bleed, IPS glow, and clouding
Measure how fast you react with a browser-based millisecond reflex test
Check webcam quality, resolution, and snapshots
Count how many spacebar presses you can make in 5, 10, or 30 seconds
27 tools · 4 Web Stories
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Monitor reality check
1000Hz Is Real. Worth $999?
LG's UltraGear 25G590B is the first native 1000Hz 1080p monitor. Check the fine print first.
01 / 10
Phone buying guide
PWM-sensitive? Test the phone, not the promise
Display specs narrow the shortlist, but no OLED is comfortable for everyone.
01 / 10
Screen flicker test
Your screen may be flickering
Many displays dim by switching the backlight on and off hundreds of times a second.
01 / 10
Monitor check
Dark scenes losing detail?
Your monitor may be turning several near-black shades into one flat black.
Source-based buyer analysis of the first native 1000Hz monitor: verified specs, the 1 ms GtG contradiction, the MBR Pro versus G-SYNC/FreeSync trade-off, dated prices against 480Hz OLED and dual-mode alternatives, and five delivery-day browser tests.
