Countdown Timer
Set hours, minutes and seconds, and get an alert when the time is up.
0:05:00
Keep this tab open. Browsers may only allow sound after you press Start.
Enter a time, press start, and the timer counts down and sounds an alert when it reaches zero. The remaining time is shown in the browser tab title, so you can switch to other tabs and still see it.
Use the presets for common durations, or enter your own.
How countdown timer works
When you press start, the timer records the exact finish time and calculates what is left each time it updates. This keeps it accurate even when the browser slows down background tabs.
The alert is a short tone generated in the browser. Browsers only allow sound after you have interacted with the page, so start the timer with a tap or click. Keep the volume up and the tab open.
Worked example: a 25-minute focus block
Enter 0 hours 25 minutes 0 seconds and press start.
At zero the timer shows the finished message and plays the tone. Use reset to run it again.
When to use this tool
- Cooking and baking.
- Study, exercise and meeting time limits.
- Short breaks and screen-time limits.
Common mistakes to avoid
- Closing the tab. The timer only runs while the page is open.
- Muting the tab and missing the alert. Check the title bar as well as the sound.
- Relying on it for anything safety-critical, such as medication or a food safety limit. Use a dedicated device.
Frequently asked questions
- Will the timer still work if I switch tabs?
- Yes, as long as the tab stays open. The remaining time appears in the tab title.
- Why did I not hear the alert?
- Check the device volume and that the tab is not muted. Browsers require a click or tap on the page before they will play sound.
- Can I set a timer for more than 24 hours?
- The fields accept up to 99 hours.
Learn more
Related tools
- Online StopwatchA simple stopwatch with lap times, running in your browser.
- Pomodoro TimerWork in focused sessions with short breaks. Adjustable lengths, automatic switching and a sound alert.
- Password GeneratorCreate strong random passwords in your browser, with adjustable length and character sets.
- Word CounterCount words, characters, sentences and paragraphs, with reading and speaking time.
- QR Code GeneratorCreate a QR code for a link or text, then download it as PNG or SVG.
- Image CompressorShrink JPEG, PNG and WebP images in your browser. Choose quality and size, and download the result.
Results are for information only and are not financial, legal or medical advice. The calculation logic is covered by automated tests, and examples on this page are worked out and re-checked before publishing. Spotted a mistake? Tell us.