Screen guides

Full device checkStep by step, with a report — great before buying used Device & browser infoScreen, browser, features and permissions Video call readinessCamera, mic, speakers and WebRTC Internet speed testDownload, upload and ping Latency & jitter testHow steady is your connection? Phone hardware testSpeakers, microphone, vibration, multi-touch and motion sensors. Touch screen testFind dead zones and ghost touches across the whole screen. Refresh rate testCheck if your screen really runs at 90, 120 or 144Hz. Backlight bleed testSpot light leaking from the edges of an LCD screen. Ghosting testSee trailing and motion blur on moving objects. Burn-in testReveal shapes burned into an OLED screen. Contrast testCheck black level and white saturation with 20 gray steps. PPI calculatorPixel density, aspect ratio and real screen size. Keyboard testPress every key to find dead or sticky keys. Mouse testCheck buttons, the wheel and unwanted double clicks. Sound testLeft / right channels, bass, frequency range and polarity. Camera testCheck that your webcam works and see its real resolution. Dead pixel locatorMark faulty pixels and download a map for your warranty. Viewing angle & gammaCheck gamma and how colors shift from the side. Screen rulerA real-size ruler in cm and inches. White & color screenFull-screen white, black and solid colors. Mic testLive level meter and a 5-second recording. Gamepad testButtons, triggers and stick drift check. Click speed test (CPS)How many clicks per second can you do? Reaction time testMeasure your reflexes in milliseconds.

Fix a stuck pixel for freeBring a stuck red, green or blue pixel back with rapid color cycling. Dead pixel test onlineSpot dead and stuck pixels in under a minute with full-screen colors. Color banding testCheck gradients for visible steps and learn how to reduce banding. Check a used phone screen before you buyA complete checklist for testing a second-hand phone's screen. OLED vs LCD: which screen is better?OLED vs LCD explained simply: contrast, brightness, burn-in, flicker, lifespan and price — and how to test each type of screen. How to tell if your phone screen is originalSigns that a phone screen was replaced with a non-original part: color tint, brightness, black levels, touch, fingerprint sensor and system warnings. What does 120Hz mean? Refresh rate explainedRefresh rate explained: what 60Hz, 90Hz, 120Hz and 144Hz mean, how it differs from FPS and touch sampling rate, and how to check your screen's Hz. OLED burn-in: causes, test and preventionWhat OLED burn-in is, how it differs from temporary image retention, how to test for it, and practical ways to prevent it on phones, TVs and monitors. Backlight bleed vs IPS glowLearn the difference between backlight bleed and IPS glow on LCD monitors and laptops, how to test for each, and when it counts as a defect. Response time and ghosting explainedWhat monitor response time means (GtG vs MPRT), why ghosting and overshoot happen, how BFI helps, and how to check motion clarity in your browser. Touchscreen not responding? Causes and fixesWhy a touchscreen stops responding or registers ghost touches, and step-by-step fixes: cleaning, screen protectors, chargers, restarts and when it's hardware. How to clean a screen safelySafe screen cleaning for phones, laptops, monitors and TVs: what to use, what to avoid, and why cleaning comes first before any dead pixel test.