This timer is set for 90 minutes of focus and a 20-minute break, for one long block on a single demanding task. The popular idea of a built-in 90-minute brain cycle is shakier than it sounds, so treat 90 minutes as an upper limit to try, not a rule, and stop early if you're fading.
When does a 90 minute focus session make sense?
When there’s one task, it’s hard, and it takes a long time to get into. Drafting a chapter, chasing a stubborn bug, practising an instrument, working through a big design problem.
There’s a useful marker in Ericsson and colleagues’ 1993 study of expert musicians. The violin students they followed practised in sessions averaging 80 minutes, and uninterrupted solo practice ran between one and one and a half hours. The authors also found that this kind of effortful practice tops out at around four hours a day. So 90 minutes is close to the upper edge of what serious practisers did in one go. Two of these is a full day’s worth of hard thinking, not a warm-up.
Is there really a 90-minute focus cycle?
Less than the internet suggests. The sleep researcher Nathaniel Kleitman proposed a basic rest-activity cycle of roughly 90 minutes that he thought ran through both sleep and waking hours.
The sleep half is well described: the Sleep Foundation puts most sleep cycles at about 90 minutes, ranging from 70 to 120. The waking half rests on smaller, mixed studies. One often cited tracked ten university students for nine hours. We couldn’t find good evidence that you carry a dependable 90-minute clock you can plan your day around. Here, 90 is a practical size for a long block, not a fact about your brain.
Why is the break 20 minutes?
A long block needs a proper stop, not a quick stretch. The American Optometric Association suggests resting your eyes for 15 minutes after two hours of continuous computer use, and a 20-second look at something far away every 20 minutes along the way.
Twenty minutes gives you time to eat, get outside, or walk somewhere that isn’t the kitchen. Make it a genuine change of scene. Scrolling at the desk for twenty minutes is just more screen with less purpose.
What if 90 minutes is too long?
Some days it will be, and that’s fine. Oregon State’s Pomodoro guide doesn’t recommend 30, 60 or 90 minute blocks, because you’re likely to get distracted or need a break before they end.
Pause is there for interruptions, and the chips switch to 50 minutes in one tap. If you’re stopping around the hour mark every time, the 50 minute timer probably suits you better. Patches won’t notice the difference; he’ll have dozed off around minute 4 either way.
Only in the app
This page is the timer and Patches. Doggydoro for iPhone is the rest of the room:
- Ten breeds to choose from, and a name of your own for yours
- Finds at the end of a session, kept in a collection
- Other apps kept out of the way while you focus, and a bedtime lock
- The countdown on your Lock Screen and in the Dynamic Island
- A room you furnish with bones earned by focusing
- Eleven sounds to work under, sticky-note tasks, Logs and your streak
Other timers
- A Pomodoro timer with a dog in it: 25 minutes on, 5 off
- A 25 minute timer: 25 minutes on, 5 off
- A 50 minute timer: 50 minutes on, 10 off
- A 15 minute timer: 15 minutes on, 5 off
- A study timer with a dog in it: 25 minutes on, 5 off
- A visual timer, with a dog for company: 15 minutes on, 5 off
- A 5 minute break timer: 5 minutes on, 5 off
Updated