Half an hour of exercise
A common way to meet the World Health Organization’s guideline of at least 150 minutes of moderate activity a week is 30 minutes on five days. A brisk walk, a bike ride or a home workout all fit: start the timer as you set off and turn back when the clock shows 15:00 for an out-and-back route. For a structured session, a 5-minute warm-up, 20 minutes of main work and a 5-minute cool-down add up to 5 + 20 + 5 = 30 minutes.
Homework, study and practice
Thirty minutes is a solid block for homework, revision or instrument practice. Decide what you want to finish before you press Start, keep your phone out of reach, and stop for a short break when the alarm rings. If you work in Pomodoro cycles, the 30 minute timer also covers the longest version of the long break.
Cooking and baking
Many dishes bake, simmer or roast for around half an hour, from trays of vegetables to rice dishes and cakes. Recipes usually give a range: set the timer for the shorter time, check, and add minutes with +1 min instead of starting over. The tab title keeps showing the time left while you do something else.
Meetings and screen time
Half-hour slots are a standard length for calls and meetings. Put the timer in full screen on a shared display and everyone can see when it is time to wrap up. Families also use a 30-minute countdown to agree on a clear limit for games or screen time.
How the timer works
Press Start, Pause or Reset at any time, and +1 min for a little extra. The alarm can be muted, and phones that support it vibrate. The screen stays on while it runs where the browser supports it, and the timer works offline once loaded. For shorter or longer blocks, try the 15 minute timer or the 60 minute timer, or set any length on the main online timer.