Test microphone input levels and device selection.

Play channel and frequency checks for your speakers.

Free online headphone test for left/right channels, stereo balance, and earcup isolation. Works with wired and Bluetooth headphones in your browser.

Verify stereo imaging with left, right, and center tones in your browser.

Confirm which speaker plays left vs right with dedicated channel tones.

Hear left/right surround positions as a stereo pan map. Browsers cannot drive true 5.1 speakers from a web page.

Estimate local mic monitoring delay with a click-to-hear loop. Comparative timing, not lab RTL.

Play a short tone and check whether your microphone hears it locally.

Measure relative ambient noise from your microphone in the browser.

Step through playback levels to verify comfort and mute behavior.

Play selectable sine tones across common hearing and speaker ranges.

Play low-frequency tones to check woofer and headphone bass response.

Play high-frequency tones to check tweeter and headphone treble response.

Verify every key press, including modifiers and special keys.

Hold multiple keys to see which combinations register without ghosting.

Measure typing speed and accuracy with a short in-browser passage.

Test mouse buttons, scroll wheel, and pointer tracking.

Measure double-click timing and catch sticky or slow double-clicks.

Estimate how often pointer-move events arrive in the browser. Not USB hardware polling Hz.

Check scroll wheel direction, delta, and smooth vs line scrolling.

Practice and verify click-drag tracking across a canvas pad.

Visual compare of pointer motion versus on-screen feedback in the browser. Not lab input lag.

Check trackpad clicks, scroll, and touch points the browser receives. Not a full macOS/Windows gesture lab.

Detect connected controllers and verify buttons via the Gamepad API.

Visualize analog stick axes, centering, and range of motion.

Check left and right trigger analog values and button presses.

Pulse gamepad rumble when the browser and controller support it. Many pads and browsers cannot vibrate from the web.

Compare standard Gamepad mapping labels with raw button and axis indices.

Measure reaction time from an on-screen cue to a gamepad press. Not USB controller poll latency.

Check stick resting drift, axis extremes, and deadzone behavior at rest.

Full-screen solid colors to visually spot dead pixels on your monitor.

Estimate display refresh from animation timing in the browser. Not a lab Hz measurement.

Watch for animation timing gaps that suggest skipped frames. Affected by CPU load and browser scheduling.

Moving patterns to judge motion clarity and blur on your screen.

Solid primary and secondary color fields for visual panel inspection.

Gray ramps and gamma reference patterns for brightness calibration checks.

High-contrast patterns and near-black/white checks for panel contrast.

Near-black shade steps to judge shadow detail and black crush.

Near-white shade steps to judge highlight detail and clipping.

Read browser HDR capability hints. Not a calibrated brightness or HDR movie test.

Smooth gradients to reveal banding, dithering, and tone steps.

Simple color-vision simulation and confusion checks, not a clinical diagnosis.

Flat gray fields to visually assess brightness and color uniformity.

Controllable flash patterns with a strong photosensitivity warning.

Compare viewport aspect ratio against common display formats.

Inspect browser, engine, and feature support details.

View screen, window, and viewport resolution with device pixel ratio.

Inspect navigator.userAgent and Client Hints when the browser exposes them.

Probe web platform API availability in your current browser.

Check Storage API estimate, persistence, and quota signals.

Verify document.cookie write, read, and delete in this origin.

Run a quick ECMAScript and runtime feature smoke test in-page.

Write and read clipboard text with the Async Clipboard API.

Check WebRTC support and gather basic peer-connection signals.

Detect WebGPU and request an adapter when the browser supports it.

Probe WebGL / WebGL2 contexts and report GPU renderer strings.

Free WebUSB test online: check Chrome/Edge support, list authorized devices, and open the USB picker. Nothing is claimed or transferred. HTTPS required.

Check Web Bluetooth availability and optionally pick a BLE device. Limited browser support; no GATT session.

Check Web Serial availability and optionally pick a port. Desktop Chromium primarily; no data is read or written.

Request MIDI access and list inputs/outputs the browser exposes.

Show your public IP address as seen by HTTP lookups and DeviceHub APIs.

Check whether your browser can reach IPv4 and IPv6 echo endpoints.

Best-effort DNS privacy smoke: public IP plus DNS-over-HTTPS. Not a full ISP DNS leak lab.

Inspect WebRTC ICE candidates for IPs that may bypass your VPN path.

Probe whether a remote host port accepts a TCP connection (via DeviceHub API).

Check HTTPS reachability, status, and timing from DeviceHub edge. Not a full SSL certificate audit.

View request headers your browser sends to DeviceHub and sample response headers.

Show Network Information hints when available. Not a speed test; often missing in Safari/Firefox.

View viewport, pixel ratio, and device capability signals.

Show how many logical processors the browser reports. Web pages cannot read your CPU model name.

Probe WebGL/WebGPU for GPU vendor and renderer strings when available.

Show a coarse device-memory hint when available. Not exact installed RAM; often missing in Safari/Firefox.

Show battery level and charging state when the browser allows it. Many browsers block this API.

Detailed screen size, available area, color depth, and orientation.

Display capability signals: color gamut, HDR media, and multi-screen hints.

Verify touch taps, moves, and maxTouchPoints on a live pad.

Visualize multiple simultaneous touch points and peak finger count.

Read acceleration when motion sensors are available. Mainly phones; iOS may ask for permission.

Show rotation rate when motion sensors are available. Mainly phones; iOS may ask for permission.

Estimate device heading from orientation events. Approximate only; not a calibrated magnetic compass.

Free magnetometer test for phones: probe magnetic field (µT) support in the browser. Honest unsupported on most desktops and Safari; try Android Chrome.

Request geolocation and show coordinates, accuracy, and timestamp.

Live device orientation alpha/beta/gamma and screen orientation type.

Detect Web NFC support on this browser and device. Mainly Chrome on Android; not a full tag reader app.

Calculate WCAG contrast ratios between foreground and background colors.

Detect prefers-reduced-motion and preview motion vs reduced experiences.

See whether the OS/browser prefers light or dark color schemes.

Check forced-colors / Windows High Contrast style media queries.

Preview WCAG text-spacing adjustments on sample copy.

Tab through sample controls and verify visible focus indicators.

List Web Speech voices and speak sample text for TTS checks.

Overview of prefers-* and related accessibility media features.

Calculate pixels per inch from resolution and diagonal screen size.

Compute print DPI from pixel dimensions and physical print size.

Estimate physical width and height from diagonal and aspect ratio.

Suggest viewing distance ranges from screen diagonal size.

Simplify width×height into a ratio and match common formats.

Find the other dimension from aspect ratio, or compute megapixels.

Convert refresh rate (Hz) to frame time and frames over a duration.