Resolution Test
Instantly shows your monitor resolution, browser viewport size, device pixel ratio (Windows display scaling), aspect ratio, and color depth. Web developers, designers, and tech support use it to debug layout issues, verify scaling, and answer 'what is my screen resolution' without digging through system settings.
What you can use it for
- Check exact viewport size while building responsive layouts
- Verify Windows display scaling (125%, 150%, etc.)
- Debug UI issues on ultrawide or Retina displays
- Confirm external monitor resolution in tech support calls
How it works
- 1. Customize. Open the Customize panel to set text, colors, theme, and animation speed to your liking.
- 2. Go fullscreen. Click Fullscreen for an immersive, distraction-free display on any screen.
- 3. Done. No login, no install, nothing to download — it runs instantly in your browser and your settings are remembered.
Frequently asked questions
What is device pixel ratio?+
It is the ratio between physical pixels and CSS pixels. A DPR of 2 means your 1920×1080 CSS viewport maps to 3840×2160 physical pixels — common on Retina and high-DPI Windows scaling.
Why doesn't viewport match screen resolution?+
The browser viewport excludes toolbars and window chrome. Go fullscreen to see the viewport at full monitor size.
More screen tests
Dead Pixel Test
Cycle full-screen colors to find dead and stuck pixels fast.
Screen Uniformity Test
Check brightness and color evenness across the whole panel.
Ghosting Test
A fast-moving object to spot motion blur and ghosting trails.
Backlight Bleed Test
Pure black screen with corner markers to spot edge light leak.
Color Banding Test
Smooth gradients to reveal color banding and bit-depth limits.
Contrast Test
Shaded squares to calibrate black levels and white clipping.
Text Sharpness Test
Tiny text samples to judge subpixel rendering and clarity.
Overscan Test
A 1-pixel grid and corner circles to fix overscan and cropping.