Speaker Polarity Test – Online Click & Listen
Generate a pop signal to determine if speakers are wired in phase. Quick stereo test.
UD5 Toolkit
Online check for your camera, microphone & speaker — 100% private, no uploads
Click "Start Camera" to begin
Start your camera to see device details.
Your camera feed is processed entirely on your device. Nothing is recorded, stored, or transmitted. The video stream stays local.
Volume: -- dB
Start the microphone test to see device details.
Speak at a normal volume. The waveform should show clear peaks. If it's flat, check your mic connection or permissions.
Start with low volume. Prolonged exposure to loud tones may damage hearing or speakers. Keep the volume at a comfortable level.
Generate a pop signal to determine if speakers are wired in phase. Quick stereo test.
Display an astigmatism dial and instructions for self-assessment. Educational, not a medical diagnosis.
Hear a word spoken by browser TTS and type the spelling. Choose difficulty or paste your own list. Great for kids. Local only.
Override your browser's geolocation to any coordinates and test how your app responds. For development and privacy testing.
Hear text spoken word by word with boundary events. See the exact index and character. Advanced TTS dev tool.
Load a video and visually check if audio aligns with lips. Use frame‑by‑frame stepping. Debug playback issues.
Toggle a screen wake lock to prevent the device from dimming or sleeping. See the lock state and learn the API.
Check if your page triggers the beforeinstallprompt event. Simulate the install flow. Debug PWA installability.
Measure your visual and auditory reaction speed. Average and best times shown. No data collected. Pure Javascript timing.
Paste your Accept‑Language header and see which languages your site should serve based on quality values. Internationalization helper.
Test how your page loads under slow, 3G, or offline conditions by intercepting fetch and applying delays. No DevTools needed.
Override your browser's geolocation to any coordinates and test how your app responds. For development and privacy testing.
Check current screen orientation and test the lock API. Useful for mobile web apps. Demo with code.
Test the Fullscreen API: request fullscreen on a colored div, detect changes, and copy the JavaScript boilerplate.
Test the Web Share API by sharing text, links, and files directly from the browser. Check compatibility and see example code.
Use your microphone to detect the dominant frequency of ambient sounds. Visualize the spectrum. Local Web Audio.
Check if your browser and display support the wider DCI‑P3 color space. See the difference with a simple test pattern.
Enter any phrase and instantly see if it's a palindrome, ignoring spaces and punctuation. Fun for word nerds.
Generate random, formatted ID numbers that match pattern rules for various countries. For testing input validation. No real data.
Pick a method, URL, headers, and body, then send an HTTP request directly from your browser. Debug APIs easily.
Generate random but realistic‑looking data arrays (users, products, orders) with typos and missing fields. For test robustness.
See the fundamental frequency (pitch) of your voice in real time using auto‑correlation. For singers and speech training. No upload.
Simple interactive eye dominance test: hold up a virtual dot and see which eye stays aligned. Educational.
Build an iframe with different sandbox flags and see live which features are blocked. For secure embedding.
Simulate random mouse moves, clicks, or keystrokes to test idle‑timeout logic. Stops when you move the mouse. Dev test.
Paste a test card number to verify Luhn algorithm, identify issuer (Visa, MC), and check length. No real data.
Play left‑only, right‑only, and frequency sweeps to test your speakers or headphones. Quick audio check.
See a live VU meter of your microphone's input level. Test if your mic is working and adjust gain. Privacy‑friendly.
Turn your webcam feed into real‑time ASCII art. Adjust density and character set. Fun for streams and demos. No upload.
Visualize audio in real time from your microphone or uploaded audio file. See the waveform dance. Uses Web Audio API locally.