24-Hour Timer
Press start. It counts down to zero and rings an alarm — nothing to download, nothing to sign up for.
About this 24-hour timer
A one-click 24-hour countdown, most often used for overnight dough and marinades, a 24-hour rule before purchases, or 24-hour challenges. It runs in your browser and rings when it reaches zero.
Twenty-four hours
A 24-hour timer counts down a full day: overnight dough rises, marinating, cooling-off periods before a big decision, and 24-hour challenges. Because a browser tab can be closed or the device can sleep, use this for a visual countdown rather than as your only alarm.
24 hours in other units
| Seconds | 86,400 |
|---|---|
| Minutes | 1,440 |
| Hours | 24 |
| Milliseconds | 86,400,000 |
| Share of a day | 100% |
Tips for using a 24-hour timer
- For overnight marinades or doughs, note the start time as well — if the tab closes you'll still know when you began.
- A '24-hour rule' before big purchases is a popular way to avoid impulse buying.
- For anything critical, also set an alarm on your phone; browser tabs can be closed by accident.
Frequently asked questions
How do I set a 24-hour timer?
Press Start above and the page counts down from 24 hours on its own — nothing to type. Need a little longer? Press +1 min while it runs, or pick a nearby duration from the list.
How many seconds are in 24 hours?
24 hours is 86,400 seconds — 1440 minutes or 24 hours. That's 100% of a day.
What is a 24-hour timer good for?
People commonly use a 24-hour timer for overnight dough and marinades, a 24-hour rule before purchases, or 24-hour challenges.
Will it keep time if I switch tabs?
Yes. The countdown is measured against your device clock rather than counting screen refreshes, so it stays accurate in a background tab and the alarm fires on time. For a timer this long, keep the device awake — some phones pause browser audio when locked.