Idle Detection API Demo - Online User Activity Monitor
Request permission and detect when the user is idle (away from keyboard). See screen lock state. For native‑like apps.
UD5 Toolkit
Generate random user events to test idle detection and session timeout logic.
click, mousemove, or keydown events on the host page, so your application code will not see them.Request permission and detect when the user is idle (away from keyboard). See screen lock state. For native‑like apps.
Generate a random, structured daily routine with time blocks. Shake up your day. Pure fun.
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.
Simulate memory page reference strings with FIFO, LRU, and Optimal algorithms. See page fault count. OS concept demo.
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.
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.
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.
Keep track of a tennis match: points, games, sets, and deuce. Supports tiebreak. Great for friendly matches. Local.
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.
Quickly test if your webcam, microphone, and speakers work correctly. See live video and audio meter. No data sent.
Generate random but realistic‑looking data arrays (users, products, orders) with typos and missing fields. For test robustness.
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.
Paste a test card number to verify Luhn algorithm, identify issuer (Visa, MC), and check length. No real data.
Adjust ISO, aperture, and shutter speed sliders and see how it affects the exposure of a sample scene. Learn photography basics.
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.
Select telescope and eyepiece parameters to see the field of view circle on a simulated night sky image.
Watch the planets orbit the Sun in a top‑down 2D view. Adjust speed and zoom. Distances not realistic; beautiful model.
Fold a virtual square paper step by step with crease lines and visual previews. Practice origami basics without wasting real paper. All canvas‑based.