Hardware Tools
Keyboard testers, screen defect detectors, refresh rate checkers, and hardware benchmark charts.
Input Device Testing
Keyboard Tester — Detect Chatter, Dead Keys & Test NKRO Free
Free online keyboard tester. Detect dead keys, check N-key rollover (NKRO), identify chatter and break contact, visualize key hold duration, test typing speed, and discover extra media keys. Real-time chord display with adjustable threshold. Works with mechanical, gaming, laptop, and wireless keyboards. 100% private, no download needed.
Mouse Tester — Test Double Click, Buttons & Scroll Online Free
Free online mouse tester. Test all mouse buttons (left, right, middle, back, forward) with real-time visual feedback. Check for double-click issues from worn microswitches — the #1 cause of mouse failure. Measure clicks per second with the CPS test, test scroll wheel precision, track cursor position, and view detailed click event logs. Works with wired, wireless, gaming mice and laptop trackpads. No download needed — runs 100% in your browser with zero data upload.
Display Testing
Dead Pixel Test — Free Online Monitor & Screen Defect Checker
Free online dead pixel tester for monitors, laptops, phones, and tablets. Display full-screen solid colors (white, black, red, green, blue, yellow, cyan, magenta) to detect dead pixels, stuck pixels, and screen defects. Test new monitors within return window, check used devices before buying, and diagnose display issues. Works on all devices with a modern browser — no download required. All testing runs locally in your browser for 100% privacy.
PPI Calculator — Screen Pixel Density & DPI Calculator
Free online PPI calculator to compute pixel density for any display. Enter screen resolution and diagonal size to calculate PPI (pixels per inch), megapixels, and aspect ratio. Includes common presets for monitors, laptops, phones, and tablets. Compare pixel density across devices to understand display sharpness. Works on all devices — no download required.
Refresh Rate Test — Free Online Monitor Hz & FPS Checker
Free online refresh rate tester to check your monitor's actual Hz. Measures real display refresh rate using requestAnimationFrame, detects frame skipping, and shows UFO motion test for visual comparison. Displays screen info including resolution, DPI, color depth, and HDR support. Works on all monitors, laptops, and phones with a modern browser — no download required. All testing runs locally in your browser for 100% privacy.
Screen Color Test — Monitor Gradient, Gamma & Uniformity Checker
Free online screen color test to check monitor quality. Test color gradients for banding, check brightness uniformity across the screen, calibrate gamma, compare two colors side by side, and test text sharpness. Includes grayscale gradient, RGB gradient, and custom gradient tests. Works on all monitors, laptops, and phones — no download required. All testing runs locally in your browser for 100% privacy.