A free web tool that keeps your screen awake during downloads, work sessions, presentations, and long-running processes. No installation needed - works directly in your browser with custom timer settings from 1-480 minutes.

• 🚫 Prevent Screen Sleep - Keep your device awake with one click
• ⏰ Smart Timer System - Set auto-sleep timers from 1 to 480 minutes (up to 8 hours)
• 🪟 Floating Window Mode - Always-on-top popup window that stays visible
• 🎨 Visual Feedback - Animated sun/moon icons show active status
• 📱 Cross-Platform - Works on desktop computers, tablets, and mobile phones
• 🌐 No Installation - Web-based tool, works directly in your browser
• 🔒 100% Safe & Private - No data collection, no permissions needed
• 🌓 Dark Mode - Easy on the eyes during extended use

• Downloads & Uploads: Set 30-60 min timers to prevent interruption during large file transfers
• Work & Study Sessions: 15-30 min focus timers to stay productive without screen dimming
• Presentations & Meetings: Keep screen active during demos and video calls
• Long Processes: 2-4 hour timers for video rendering, builds, or data processing
• Live Streaming: Prevent sleep during broadcasts and recording sessions
• AI-Assisted Coding: Extended sessions with tools like Claude Code or GitHub Copilot
• Dashboard Monitoring: Keep real-time tools and dashboards visible

NoSleep uses your browser's built-in Screen Wake Lock API - a safe, standard web technology that prevents your screen from sleeping. It's like moving your mouse occasionally, but automatic and hands-free.

1. Click the button to activate wake lock
2. Set a timer (optional) - choose 1-480 minutes or run until you manually stop
3. Keep the tab active or use the floating window feature

• Instant Activation: One click starts keeping your screen awake
• Animated Status Icons: Sun animation when active, moon when sleeping
• Flexible Timers: Quick buttons (+1, +5, +10, +30 min) or custom input
• Floating Window: Dedicated popup that stays on top and syncs with main page
• Auto-Release: Automatically allows sleep when timer expires
• Cross-Window Sync: Controls in floating window update the main page in real-time

• Chrome/Chromium 84+ (Windows, Mac, Linux, Android)
• Microsoft Edge 84+ (Windows, Mac)
• Safari 16.4+ (Mac, iPhone, iPad)
• Firefox (with additional configuration)

Browsers without Screen Wake Lock API will see a clear error message with upgrade instructions.

Note: The app automatically detects your browser's capabilities. For the best experience, use the floating window feature on supported browsers.

# npm
npm install
# pnpm
pnpm install
# yarn
yarn install
# bun
bun install

Start the development server on http://localhost:3000:

# npm
npm run dev
# pnpm
pnpm dev
# yarn
yarn dev
# bun
bun run dev

Build the application for production:

# npm
npm run build
# pnpm
pnpm build
# yarn
yarn build
# bun
bun run build

Preview the production build:

# npm
npm run preview
# pnpm
pnpm preview
# yarn
yarn preview
# bun
bun run preview

Run unit tests:

# npm
npm run test
# pnpm
pnpm test
# yarn
yarn test
# bun
bun run test

1. Visit the website at nosleep.williamchong.cloud
2. Click the main button - it will turn from green to red
3. Notice the sun animation - your screen is now staying awake
4. Click again when done to allow normal sleep

1. Click "Set Timer" below the main button
2. Choose your duration:
   • Type any number (1-480 minutes)
   • Or use quick buttons: +1, +5, +10, +30 minutes
3. Click "Start Timer" to begin
4. Relax - your screen stays awake until the timer expires
5. Cancel anytime if you finish early

1. Click "Open Floating Window" button
2. A small window appears that stays on top of other windows
3. Control from either window - they stay in sync
4. Switch tabs freely - the floating window keeps working
5. Close the floating window when done - main page takes over

• Use the floating window to avoid accidentally closing the tab
• Set realistic timers to save battery (30-60 min for downloads)
• The tab must stay open but doesn't need to be visible if using floating window
• Battery impact: Keeping screen awake uses more power - use timers wisely

• ☀️ Sun with rays: Your screen is staying awake
• 🌙 Moon: Your screen can sleep normally
• Timer countdown: Shows remaining time (e.g., "23:45 remaining")

100% Safe to Use

• ✅ No installation or downloads required
• ✅ No access to your files, camera, or microphone
• ✅ No data collection or tracking (beyond anonymous analytics)
• ✅ No account creation needed
• ✅ Uses only standard web browser APIs
• ✅ Open source - you can review the code

How It's Safe: This tool only uses your browser's built-in Screen Wake Lock API - the same technology that video players use to keep your screen on during playback. It's as safe as watching a YouTube video.

• Nuxt 3: Fast, modern web framework for optimal performance
• Screen Wake Lock API: Standard browser API for preventing screen sleep
• Document Picture-in-Picture: Advanced floating window support (when available)
• Pinia State Management: Centralized state for cross-window synchronization
• Lottie Animations: Beautiful, lightweight sun/moon animations
• Tailwind CSS: Responsive design that works on any screen size
• i18n Support: Multi-language support (English, Chinese, Japanese)

• Cross-Window Sync: Floating window and main page stay perfectly synchronized
• Smart State Management: Automatic handling of window focus and visibility
• Responsive Design: Optimized for desktop, tablet, and mobile devices
• Dark Mode: Automatic theme switching based on system preferences
• SEO Optimized: Structured data and meta tags for search engines
• Progressive Web App: Can be installed on your device for quick access

• Screen Wake Lock API - Prevents screen sleep
• Document Picture-in-Picture API - Floating window support
• Window.postMessage() - Secure cross-window communication

Try it now: https://nosleep.williamchong.cloud

Works on all modern browsers with Wake Lock API support. No signup, no download, completely free.

Q: Will this drain my battery? A: Keeping your screen awake uses more power than letting it sleep. Use timers to minimize battery impact - set them only as long as you need.

Q: What happens if I close the tab? A: The wake lock stops immediately. Use the floating window feature to prevent accidentally closing it.

Q: Can I use this on my phone? A: Yes! It works on iPhone (Safari 16.4+) and Android (Chrome 84+). The floating window may not be available on all mobile browsers.

Q: Is this better than changing my system settings? A: Yes! It's temporary and automatic. No need to remember to change settings back. When you close the tab or timer expires, everything returns to normal.

Q: Does this work offline? A: No, you need an internet connection to load the page initially. Once loaded, it works without continuous internet connection.

Want to contribute or run locally? See the development sections above for setup instructions.

Tech Stack: Nuxt 3, Vue 3, TypeScript, Pinia, Tailwind CSS, Vitest

Contributing: Issues and pull requests welcome! Check out the code on GitHub.

View License

Built by William Chong

More Projects: Visit my blog for more useful web tools and technical articles.

Keywords: prevent screen sleep, keep screen awake, download helper, no sleep timer, wake lock, screen timeout, presentation mode, prevent display sleep, keep computer awake, anti-sleep tool