Screen Wake Lock Tester - Online Keep Screen On
Toggle a screen wake lock to prevent the device from dimming or sleeping. See the lock state and learn the API.
UD5 Toolkit
Test the Screen Wake Lock API — Prevent Your Screen from Sleeping
Note: The API requires a secure context (HTTPS or localhost) to function. Most modern Chromium-based browsers fully support it.
Toggle a screen wake lock to prevent the device from dimming or sleeping. See the lock state and learn the API.
Generate a sample sleep schedule for babies 0-24 months based on age-appropriate wake windows. Nap count and bedtime suggestions. Educational reference.
Set a nap timer with optional gentle white noise or lullabies (Web Audio). Reminder to put baby down. Fully local, no ads.
Set a recurring timer that reminds you to check your posture. Desktop notification with a gentle chime. Stay healthy.
Set recurring audio/visual reminders to check and correct sitting posture. Adjustable interval and notification style. Helps reduce back pain from desk work.
Timer that reminds you to look at something 20 feet away for 20 seconds every 20 minutes. Customizable intervals and subtle sound/visual alerts.
Tap key for 15 seconds, calculates BPM. Quick resting heart rate check. Manual, no hardware.
Set a 20, 30, or 45‑minute countdown to simulate a technical interview. Hidden/unhidden. Boost your prep.
Wait for the box to turn green, then tap as fast as possible. Measure milliseconds. Compete with friends.
Set timer for incubation period with temperature guide. Track hours for optimal tanginess. Homemade yogurt.
Visual and audio beat at 100‑120 compressions per minute. 30 compressions timer. For training and emergencies.
Countdown timer with alerts for boiling pacifiers, bottles, or pump parts. Follow recommended times. Local audio alarm.
Enter a URL and a user‑agent to see if it is allowed or blocked by the robots.txt file. Quick bot validation.
Hash passwords using the bcrypt algorithm with configurable cost factor. Also verify a password against a stored hash. All local.
Enter completed chores/reading minutes to calculate earned screen time. Customizable rates. Local tracking.
Play a frequency sweep from 20Hz to 20kHz. See where your hearing cuts off. Headphones needed.
Convert traditional cooking time to electric pressure cooker time. Reference chart.
Play pure tones at various frequencies to estimate your hearing range. Simple and educational.
Play a sweep from 20Hz to 20kHz. Test your speakers and your hearing. Simple and effective. Web Audio API.
Perform gestures on a canvas and see them detected in real time. Logs swipe direction, pinch scale, and rotate angle.
Design a custom CSS toggle switch (checkbox). Adjust size, colors, icons. Copy the pure CSS code. No JavaScript.
Get a random UI challenge (e.g., 'Design a checkout flow for a plant shop') to practice your skills. All local.
Fetch a site’s HSTS header and validate its syntax, max‑age, and subdomain flags. Ensure your site enforce HTTPS.
Select an emoji that matches your mood and log it to a simple calendar. Self‑awareness tool. Local only.
Enter your altitude to adjust canning processing times or pressure. Prevent botulism. Based on USDA guidelines. Essential for home canners.
Enter child's stats and compare to typical rear-facing, forward-facing, and booster seat requirements. Reference tool.
See a live VU meter of your microphone's input level. Test if your mic is working and adjust gain. Privacy‑friendly.
Evaluate password strength through a short interactive story where each character set adds lines to a narrative. Educational fun.
Get an endless supply of clean, family‑friendly knock‑knock jokes. Click for a new one. No ads, just laughs.
Tap any key to measure beats per minute. Displays average BPM and beat interval in milliseconds. Essential for DJs and music production. No extra permissions.