Frequently Asked Questions

Display Test Online is a free, browser-based hardware diagnostic platform that provides professional-grade instruments for evaluating computer displays and touchscreen digitizers. It includes twelve specialized tools covering sub-pixel analysis, OLED uniformity, HDR luminance, color gamut profiling, multi-touch precision, and latency benchmarking. All tests execute entirely within your browser using WebGL, Canvas 2D, and Web APIs — no installation or account required.

Yes, Display Test Online is completely free to use with no paywalls, subscriptions, or hidden fees. Every diagnostic instrument in the suite is available to all users without registration. The project is open-source and community-driven.

No downloads, installations, or browser plugins are required to use Display Test Online. All tools run natively in your browser using standard Web APIs including WebGL, Canvas 2D, the Pointer Events API, and performance.now(). Simply open the page and start testing immediately.

The Sub-Pixel Analyzer renders a series of WebGL GLSL ES 3.0 shader-driven test patterns that target individual red, green, and blue sub-pixels within each display pixel. By illuminating specific sub-pixel triplets, it allows you to identify stuck sub-pixels, sub-pixel layout (RGB, BGR, RGBW), and clarity rendering anomalies according to ISO 9241-307 standards.

PPI (Pixels Per Inch) is a measure of pixel density — how many pixels are packed into each inch of a display panel. Higher PPI means sharper, more detailed imagery because individual pixels become too small to resolve with the naked eye at typical viewing distances. Display Test Online's PPI Calculator computes exact pixel density from your display's native resolution and panel size.

OLED burn-in (permanent image retention) occurs when static UI elements are displayed at high brightness for extended periods. Modern OLED panels include pixel-shift and screen saver mitigations. Display Test Online's OLED Burn-In Risk tool evaluates your display's susceptibility using sustained static patterns and reports estimated long-term risk.

VRR (Variable Refresh Rate) allows a display to dynamically adjust its refresh rate to match GPU frame output, eliminating screen tearing and reducing stutter. Display Test Online's VRR Sync Engine generates visual animations that ramp up and down across your display's supported VRR range to visually verify synchronization.

QD-OLED uses a blue OLED emitter layer combined with quantum dot conversion for extremely high color gamut coverage (>99% DCI-P3). WOLED uses a white OLED stack with color filters, offering excellent uniformity and deep blacks. Both exhibit pixel-level dimming and infinite contrast.

Display Test Online's Color Gamut & ICC Profile tool measures color primaries and generates an ICC v2-compatible profile file with a SHA-256 checksum computed via the Web Crypto API, which you can download and install in macOS or Windows color management settings.

No. All processing in Display Test Online happens 100% client-side within your browser. We operate zero telemetry servers and transmit zero diagnostic data to any external endpoint.

Display Test Online works on all modern evergreen browsers including Chrome 100+, Firefox 100+, Safari 16+, and Edge 100+ on desktop and mobile.

Accuracy varies by test type and is subject to browser environment capabilities. While not replacing dedicated hardware colorimeters, they provide precise relative benchmarks and diagnostic metrics.

The Keyboard Tester Hub logs microsecond-level timestamp deltas between key release and subsequent keypress events using high-resolution performance.now() timers. If a re-trigger occurs below 35ms, it flags a switch chatter alert.

N-Key Rollover (NKRO) guarantees that every key pressed simultaneously registers independently without dropouts or ghosting, unlike membrane keyboards which suffer key blocking.