90/30 Deep Work Timer
90-minute focus · 30-minute break · auto-repeats. No signup needed.
90 min focus · 30 min break · auto-repeats. Save your streaks in the full app.
The 90/30 cycle aligns with the body's ultradian rhythm — roughly 90-minute waves of alertness followed by a natural dip. Ninety minutes of single-tasked deep work, then a real 30-minute recovery, is a favourite of researchers and peak performers.
This clock runs the 90/30 cycle automatically and starts on one click. Treat the focus block as a "do not disturb" signal to yourself.
Tip: Guard the recovery as fiercely as the focus. A genuine 30-minute break — walk, eat, rest — is what makes the next 90-minute block just as sharp.
Frequently asked questions
What is the ultradian rhythm?
A natural cycle of roughly 90 minutes of higher alertness followed by a dip — the basis for the 90/30 work rhythm.
Is 90 minutes too long to focus?
For deep, single-tasked work it aligns with one natural focus wave. If it feels long, start with 50/10 and build up.
Does it require an account?
No. It's free to use immediately; accounts only save your history.
More Pomodoro timers
Prefer a plain countdown? Try the 25 minute timer, or open the full FlipFocus app for meditation, streaks, and sounds.