30 Minute Timer
A 30:00 countdown is ready to go: press Start (or Space) and an alarm rings when the half hour is up. It keeps accurate time in a background tab, and you can add or remove a minute or switch to 15, 20, 25, 45 or 60 minutes.
Shortcuts: Space start / pause · R reset · F fullscreen. Keep this tab open; the timer stays accurate in the background.
How to use the 30 Minute Timer
- Press Start (or the Space bar). The 30:00 countdown begins immediately.
- Adjust if needed: use +1 min or −1 min, or pick a preset such as 25 or 45 minutes.
- Choose an alarm tone and volume and press Play test sound. Tick the halfway chime if you want a reminder at 15:00.
- Go fullscreen with the Fullscreen button or F to show the timer to a room or class.
- When the alarm rings, press Stop alarm or Space, or +1 min to snooze. Press R at any time to reset.
30 minutes at a glance
| Unit | 30 minutes equals |
|---|---|
| Seconds | 1,800 s |
| Milliseconds | 1,800,000 ms |
| Hours | 0.5 h (half an hour) |
| Share of a day | 1/48 of a day (about 2.08%) |
| Pomodoros | About one Pomodoro (25 min work + 5 min break) |
Ideas for a 30-minute timer
- Deep work sprint: close other tabs, put your phone away and work on one task until the alarm rings. A 30-minute block is long enough to get into focus but short enough to start without dread.
- Exercise: many public health guidelines recommend at least 150 minutes of moderate activity per week, which is 30 minutes on five days.
- Study sessions: study for 30 minutes, then test yourself for a few minutes on what you just learned.
- Power nap: naps of 10–30 minutes help many people feel more alert without the grogginess of longer sleep.
- Cooking and baking: roasting vegetables, baking a tray of muffins or simmering a sauce often takes about half an hour.
- Classroom and meetings: time a test, a group activity or a 30-minute meeting slot in fullscreen so everyone can see the remaining time.
- Screen-time limits: give kids (or yourself) a clear, visible end to gaming or social media.
Common timer lengths compared
| Preset | Seconds | Typical use |
|---|---|---|
| 15 minutes | 900 | Short break, quick tidy-up, stand-up meeting |
| 20 minutes | 1,200 | Power nap, the 20-20-20 eye break routine reminder, a short run |
| 25 minutes | 1,500 | One Pomodoro work interval |
| 30 minutes | 1,800 | Study or work block, workout, meeting |
| 45 minutes | 2,700 | School lesson, longer workout, slow-cooked dishes |
| 60 minutes | 3,600 | Exam, lecture, deep work session |
The countdown uses your device's clock, so it stays accurate even if the browser slows down timers in background tabs. For the most reliable alarm, keep the tab open, the volume up and the device awake.
Making the alarm reliable
Browsers only allow web pages to play sound after you have interacted with them, which pressing Start does, so the alarm can ring even if you switch to another tab. Use Play test sound once to check the volume, and choose Repeat until stopped if you might be out of the room. On phones, the operating system may suspend a page when the screen turns off; plug the phone in and keep the screen on, or turn on the browser notification as a backup. If you close the tab the timer stops, because nothing is stored on a server.
Frequently asked questions
How do I set a timer for 30 minutes?
Just press Start or the Space bar. The timer is already set to 30:00, counts down to 0:00 and then plays an alarm until you press Stop alarm.
Will the timer keep running if I switch tabs or lock my screen?
It keeps running while the tab is open, even in the background, because it is based on the system clock rather than on counting ticks. If your device goes to sleep the browser may pause sound, so keep the device awake for the alarm. The time left is also shown in the tab title.
How long is 30 minutes in seconds?
30 minutes is 1,800 seconds or 1,800,000 milliseconds. It is half an hour (0.5 hours).
What is the halfway chime?
If you tick Soft chime at the halfway point, a short, gentle two-note chime plays when 15 minutes are left (or half of whatever time you set). It is handy for exams, presentations and workouts.
What can I do in 30 minutes?
Thirty minutes fits a focused study or work block, a brisk walk or run, a power nap of 20–30 minutes, a quick meal prep, a short meeting, or the recommended daily minimum of moderate exercise in many health guidelines.
Can I get a notification when the time is up?
Yes. Tick Notify me when time's up and allow notifications when your browser asks. You will see a system notification even if the browser is minimised, as long as the tab stays open.
What are the keyboard shortcuts?
Space starts, pauses and resumes the timer (and stops the alarm), R resets it and F switches fullscreen on and off. Esc also leaves fullscreen.