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How to Test a New TV for Dead Pixels and Uniformity

TVs are big, so defects are easy to miss — and easy to spot once you know what to display.

Get a test pattern on screen

  • Smart TV: open the built-in web browser and load this site.
  • No browser: cast or mirror from a phone, or use a USB stick with solid-color images.

The tests

  1. Pixels — full-screen red, green, blue, white, and black via the Color Test.
  2. Dirty screen effect (DSE) — a 5% gray or Brightness Uniformity field shows vertical bands and blotches that ruin panning shots in sports.
  3. Backlight/blooming — on LED/Mini-LED sets, the Blooming Test reveals halos around bright objects on black.
  4. OLED black — on OLED, a Black Screen should look truly off, with no glow.

Viewing distance matters

Step back to your normal seating distance before judging. A single pixel invisible from the couch isn't worth a return; a gray-uniformity band visible across the room is.