ScreenTest.Pro

Phone screen test

The whole screen stack, tested from the phone's own browser: the touch layer, the pixels, the OLED's history, and whether the numbers on the box are the numbers on the glass.

Run it

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Steps 3–5 of the full check: burn-in, refresh rate, resolution.

The five-minute phone screen check

  1. Touch grid — run the touch test and paint the grid to 100%, edges and corners included. Dead strips and ghost touches are the most expensive faults on a used phone — and the first thing a bad screen replacement shows.
  2. Solid colors — run the dead pixel test and scan each color fullscreen. A dot that ignores the color behind it is a defective pixel; a colored line is a failing panel connection.
  3. Burn-in grays — run the burn-in test and pause on gray. Ghosts of a keyboard, status bar or navigation buttons mean the OLED has uneven wear — permanent, and a fair price negotiation.
  4. Refresh rate — run the refresh rate test. A phone sold as 120 Hz should measure 120 with motion smooth at speed — a 60 reading usually means a power-saving cap, but on a repaired phone it can mean a downgraded replacement panel.
  5. Resolution and density — run the resolution checker and compare against the model's spec sheet. A mismatched resolution on a repaired phone is the classic sign of a cheaper aftermarket screen.

Why these five

Each one catches a fault the others can't. The touch grid reads the digitizer, which fails independently of the picture — most dramatically after drops and cheap repairs. The solid colors read the pixels themselves. The gray fields read the panel's history: OLED wear is the one fault that tells you how the phone was used before you held it. And the two measurement pages read the spec sheet against reality, which is where downgraded replacement panels and quiet power caps get caught. Five minutes covers the screen end to end — on a used phone, run them in the order above and in front of the seller.

FAQ

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How do I test a used phone screen before buying?

Five checks, five minutes, in the order above: touch grid to 100%, solid colors for dead pixels, gray fields for burn-in, measured refresh rate, and resolution against the spec sheet. Everything runs in the phone’s own browser with nothing installed — which matters when the phone isn’t yours yet. A seller who won’t give you five minutes with a browser open is answering a question you didn’t ask. The deeper why is in How to test a used screen before buying.

My screen was replaced — how do I tell if the new one is good?

Replacement screens range from original-quality to barely adequate, and the difference hides exactly where these tests look. Run the touch grid to the edges (cheap digitizers die there first), check the measured resolution against the model’s spec, confirm the refresh rate didn’t drop from 120 to 60, and view a gray field for tint and blotches — aftermarket OLEDs and LCD-for-OLED swaps show themselves on uniform gray immediately.

Why does my 120 Hz phone measure 60 Hz?

Almost always software saving power: battery saver, a per-app cap, or the adaptive mode deciding a static browser page deserves 60. Charge the phone, disable battery saver, set the display mode to high or standard (not adaptive) and scroll during the measurement — adaptive panels ramp up under motion. If it still pins at 60 after that, then the panel or a repair is the story. Full detail on the refresh rate test page.

Do phones get OLED burn-in?

Yes — nearly every current phone is OLED, and the static elements phones draw all day (status bar, keyboard, navigation gestures bar) are exactly the burn-in recipe. It shows years in, as ghost lettering on uniform mid-tones. The burn-in test paused on gray finds it in seconds; prevention is the usual mix of auto-brightness, dark mode for static apps, and not pinning one app at full brightness for hours daily.

The screen glass is cracked but the picture works — is that fine?

Sometimes, briefly. The glass, digitizer and panel are laminated together on modern phones, so a crack that spares the picture still tends to grow into the touch layer — ghost touches and dead strips along the crack line are the usual next act, and moisture now has a way in. Run the touch test around the crack today and again in a month; degradation between runs is your repair-now signal.