Global Meeting Time Finder - Online Multi‑Zone Overlap Tool
Select cities and see a 24-hour grid highlighting compatible meeting times. Drag to find a slot that works for everyone. Daylight saving aware.
UD5 Toolkit
Set custom times to automatically switch between dark and light mode on your website
Tip: Add .dark-mode CSS styles to customize your dark theme colors.
An Auto Dark Mode Scheduler is a tool that automatically switches your website between dark and light color themes based on a custom time schedule you define. It enhances user experience by reducing eye strain during nighttime browsing while maintaining readability during daylight hours. Unlike system-level dark mode (prefers-color-scheme), a scheduler gives you precise control over when the switch happens.
The tool generates a lightweight JavaScript snippet that runs in the visitor's browser. It checks the local time every minute and compares it against your configured start and end times. When the current time falls within the dark mode window, a CSS class (dark-mode) is added to the <html> element, triggering your dark theme styles. The scheduler correctly handles schedules that cross midnight (e.g., 10 PM to 6 AM).
Yes! For the best user experience, you can combine time-based scheduling with the CSS prefers-color-scheme media query as a fallback. Use the scheduler to override the system preference during specific hours, or let the system preference take over when no schedule is active. The generated code can be easily extended to check both conditions.
If JavaScript is disabled, the time-based scheduler won't function. However, you can provide a fallback using the CSS prefers-color-scheme media query, which works natively in modern browsers without JavaScript. We recommend implementing both: the scheduler as the primary method and the media query as a graceful fallback for non-JS users.
The scheduler uses the visitor's local time (via the browser's Date object), meaning it automatically adapts to each user's time zone. If a user in New York visits your site at 8 PM EST, they'll see the dark mode if your schedule includes that time — while a user in London at the same moment may see light mode based on their local time.
Once the dark-mode class is added to your <html> element, you can define corresponding CSS rules. For example: .dark-mode body { background: #1a1a2e; color: #e0e0e0; }. Use CSS custom properties (variables) for a more maintainable approach — define your color palette under :root for light mode and override them under .dark-mode for dark mode.
Yes! This Auto Dark Mode Scheduler is completely free to use. You can generate unlimited code snippets, test different schedules in the live preview, and copy the JavaScript code to embed on any website — personal or commercial. No registration or payment is required.
Reduce blue light exposure during evening hours. Dark mode at night helps minimize eye strain and may improve sleep quality for your visitors.
The generated JavaScript is under 1KB, runs efficiently with minimal CPU usage, and uses setInterval with 60-second checks for optimal performance.
Works on all modern browsers including Chrome, Firefox, Safari, and Edge. Respects user time zones automatically with no server-side configuration needed.
Select cities and see a 24-hour grid highlighting compatible meeting times. Drag to find a slot that works for everyone. Daylight saving aware.
Set watering schedules for multiple plants with visual alerts. Shows which plants need water today based on last watered date. Data stored locally.
Enter processes and see how different scheduling algorithms handle them. Gantt chart generation. OS course helper.
Define a set of colors for light and dark themes. Get the CSS custom properties snippet. Toggle live.
Implement a dark/light theme toggle that respects prefers‑color‑scheme. Copy the complete JavaScript and CSS.
Toggle between light and dark mode for a demo page. See how to use the media query. Copy the pattern.
Generate the <meta name='color‑scheme'> tag and CSS property to enable native dark/light rendering. Quick copy.
Schedule tasks with user‑visible, user‑blocking, or background priority. See execution order and delays. Modern web perf.
Design a light and dark theme by picking colors for backgrounds, text, and links. Get the CSS for both themes. Local.
Design a custom CSS toggle switch (checkbox). Adjust size, colors, icons. Copy the pure CSS code. No JavaScript.
Build cron expressions using a visual editor with dropdowns. See human-readable description and next run times. Easier than raw cron.