Panel & Backlight
Contrast Test
Black-and-white checkerboards to judge black/white separation.
▶ Start full-screen test4 × 4← / → or tap the sides to switch · Esc to exit
How to use
- 1Click Start and view the checkerboard full-screen.
- 2Use ← / → to change the grid density (4×4 up to 32×32).
- 3Black squares should stay deep black and white squares bright, with crisp edges between them.
- 4Press Esc to exit.
FAQ
What should I look for?
Clean separation between black and white with sharp borders. Greyish blacks indicate low contrast; fuzzy edges can indicate poor sharpness or scaling.
Can this measure my contrast ratio?
No. A contrast ratio is a measurement of light output and needs a meter. This is a visual check: it shows whether black stays deep right next to bright white, which is what a high or low contrast ratio looks like in practice.
Which panel types do best?
OLED, because each pixel switches off: its black squares stay fully dark beside white ones. Among LCDs, VA panels typically reach 2,500:1 to 5,000:1 and IPS around 1,000:1, so IPS blacks look noticeably greyer in a dark room.
Tips
- Black squares should stay inky black; a grey wash means low contrast or raised black level.
- Fuzzy edges between squares point to scaling or sharpness issues, not contrast.
Related tests
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Related guides
Learn more about what this test reveals and how to act on the results.
Contrast Ratio Explained: What the Numbers Really MeanStatic, dynamic and "infinite" contrast ratios measure very different things. Here's what each panel type really delivers and how to judge it yourself.Why Do Blacks Look Grey? Full vs Limited RGB RangeWashed-out blacks or crushed shadows over HDMI are often an RGB range mismatch, not a bad panel. Here's how to spot it and how to set it right.Gamma Explained: Why Your Shadows Look WrongGamma controls how brightness is distributed between black and white. Here's how to check yours, why 2.2 is the standard, and how to set it.IPS vs VA vs TN vs OLED: Which Panel Should You Get?Color, contrast, response speed and viewing angles compared across all four panel types, with the right pick for gaming, work and movies.