Phone Screen Test
A full phone-screen checkup — dead pixels, color, focus and more — plus refresh-rate and touch tests, all built for phones and tablets.
Start with the solid-color test, then work through all 8 checks in order. Tap the screen to move to the next test project. a total of 32 steps
- Tap anywhere on the screen to move to the next view; when the current check finishes it advances, and exits fullscreen once all checks are done.
- Swipe left to go back to the previous view; it stops at the very first view.
- After entering fullscreen, the top title and bottom controls auto-hide so the screen stays unobstructed.
- Touch the bottom-centre zone to bring the title and controls back; move away and they hide again.
- The breathing test ends and exits fullscreen automatically after about 10 seconds.
Phone screen tests
Why choose the phone screen test?
Built for phone screens
Big tap targets, swipe navigation and fullscreen tap-to-advance — the full display checkup, reworked for hands.
Covers the real checkpoints
Dead / stuck pixels, backlight bleed, color accuracy, focus and dark-level detail in one place, plus refresh-rate and touch tests.
Fullscreen immersion
Request fullscreen and slide finger to move to the next view; on iPhone where the API is restricted it still uses a full-viewport overlay.
Free, private, no install
Nothing to download, no account needed — everything runs in your browser. No screen image ever leaves your device.
How to start testing
- 01 · Open in a phone browser
Landscape + max brightness gives the most accurate results; switch off night / dark-mode color filters first.
- 02 · Run the display check
Tap the big button (or a single tab). The overlay fills the screen and steps through colors, backlight, grayscale and grids.
- 03 · Judge and record
Tap / swipe left to advance, swipe right to go back; mark any dead or bleeding spots, and screenshot anything unusual as evidence.
Frequently asked questions
What’s a dead pixel, and how is it different from a bright or stuck pixel?
A dead pixel is a spot that fails to change color. Bright pixels stay white or colored on dark screens, dark / stuck pixels stay black on light screens, and tinted pixels hold a single color like red, green or blue. A few dark pixels are usually more noticeable, and most manufacturers set warranty thresholds — check your official after-sales policy.
Is backlight bleed a quality defect?
Slight bleed is within normal manufacturing tolerance on many OLED / LCD panels, especially visible in a fully dark room and at wide angles. If the bleed is large and clearly visible at normal viewing angles and brightness, contact support or get it serviced.
How long does the test take?
The full display check takes about 2–3 minutes; adding the refresh-rate and touch tests brings it to around 5 minutes. Test only the items you care about if you’re in a hurry.
Which phones and browsers are supported?
iOS and Android default browsers plus Chrome, Safari and Edge, with no plugins needed. Older devices or browsers may measure refresh rate less accurately — the system browser usually gives the best result.
Can a web test find every screen hardware problem?
It covers the common visible issues — dead pixels, bleed, color, touch and refresh rate — so it catches most problems you can see with your eyes. It can’t fully replace professional gear; for deeper faults (ribbon cables, display driver IC) go to official service or a repair shop.
What should I watch during testing?
Test for dead pixels and bleed in a dim room without direct light, and raise brightness to max to spot anomalies more clearly; turn off night mode and color filters for the color and uniformity checks.
Phone screen types
By light source
- OLED / AMOLED: each pixel lights itself — true blacks, big contrast, thin and fast, but watch for burn-in.
- LCD: backlight + liquid crystal — natural colors and no burn-in, but weaker blacks / contrast and slightly thicker.
- Mini-LED / LTPO: zone backlight and adaptive refresh for flagship screens.
By shape & camera cutout
- Flat / curved: flat resists accidental touches; curved feels more immersive.
- Punch-hole / waterdrop / under-display: ways to hide the front camera — under-display trades some light and photo quality for a full unbroken screen.
- Foldable: the shape-shifting flagship direction.
Core metrics
Detail & image quality
- Resolution: FHD+ / 2K·QHD+ — higher means more detail on screen.
- PPI (pixels per inch): resolution divided by size — the higher, the finer; individual pixels vanish at normal viewing distance.
- Brightness / contrast / ΔE accuracy: drive outdoor visibility, dark-scene contrast and color fidelity — lower ΔE is more accurate.
Smoothness & eye comfort
- Refresh rate: 60 / 90 / 120 / 144 Hz — higher feels smoother when scrolling.
- LTPO adaptive: drops to 1 Hz on static content, boosts back up when scrolling — a smoothness / battery balance.
- Touch sampling rate: how often the screen samples your finger — higher = more responsive, key for gaming.
- Dimming: DC dimming avoids flicker; high-frequency PWM (1440Hz+) is easier on the eyes.
Marketing specs are theoretical peaks — system scheduling and power modes make real numbers float. Measure the live refresh rate, sampling rate and color here.
Screen anatomy
Inside-out: every part has a job
- Display Driver IC — the "translator": turns image signals into driving signals the panel can use.
- Emitting layer: decides color, contrast and power draw.
- Touch layer: catches every tap (in-cell or add-on touch module).
- Protection layer: Gorilla Glass generations keep pushing scratch and drop resistance.
Who makes the panels
- Samsung Display, BOE and Visionox are the main OLED panel suppliers.
- The same model can vary slightly between suppliers — real-world testing beats spec sheets.
Common faults, self-checked
Touch problems
- Drift / mis-aimed taps: taps land off-target — often touch-layer age, a bad screen protector, or moisture.
- Dead / laggy zones: the grid test reveals borderline areas you can't see in photos.
Display problems
- Burn-in / ghosting: OLED holds a static image (status bar, nav bar) too long → uneven pixel aging.
- Backlight bleed / color blotch: more common around OLED edges → panel QC or long heavy use.
Suspect a fault? Run the display + touch checks here first — pinpoint whether it's the panel, the touch module or a setting before sending it to service.
Care & buying guide
Keep it healthy
- Clean with a soft dry cloth (phone off); avoid alcohol or chemical cleaners on the panel.
- Rotate wallpapers and keep auto-brightness on to slow OLED burn-in.
- A screen protector / tempered glass guards against scratches; avoid long direct-sun heat.
Pick by how you use it
- Browse / social: an FHD+ OLED at 90Hz is plenty.
- Gaming: 120Hz+ refresh paired with a high touch sampling rate.
- Video: color, contrast and peak brightness — OLED with a wide gamut.
- Long reading / office: prioritize eye-comfort dimming and low-blue-light modes.
After buying, verify the real refresh rate, gamut, dead pixels and touch response here — catch individual QC issues early.