90 Minute Focus Timer

A free 90 minute focus timer for real deep work.

The hardest, most valuable work needs a long runway. A 90 minute focus timer gives you one full wave of attention to dig into a problem, then a real rest before the next wave.

Why 90 minutes? The ultradian rhythm

Your body does not run at one flat level all day. It moves in waves. Sleep researcher Nathaniel Kleitman described a roughly 90 minute cycle that runs through the night in our sleep stages and continues, in a quieter form, while we are awake. These waves are called ultradian rhythms.

In the waking version, you ride about 90 minutes of rising and peak alertness, then dip into a trough where focus gets harder and your mind wants a break. Try to push through that trough and you grind. Honor it with a rest and the next wave comes back strong. That is why a 90 minute block lines up so well with how attention actually works. You ride one full wave, then recover.

The exact number is not magic, and it varies from person to person. Treat 90 minutes as a strong default, not a rule. Some days you will feel the dip at 75 minutes, some days you will sail past 100. The point is to work in waves and rest between them, not to push in a straight line until you are fried.

How to run a 90 minute focus block

GoFlow gives you three ways to do it, so pick the one that fits how you like to work.

• 90/15 Pomodoro: work 90 minutes, then GoFlow rolls into a 15 minute break on its own. Best for a repeating deep work rhythm.
• Fixed limit: set a hard 90 minute cap for one block, like a single morning session before a meeting.
• Open stopwatch: if you want to ride the wave by feel, run the open timer and stop when your focus dips, around the 90 minute mark.

How to protect the 90 minutes

A long block only pays off if it stays unbroken. One slip to email or a feed can cost you 20 minutes of getting back into it, which wrecks the whole wave. So clear the path before you start. Phone in another room. One task, named out loud. The free Focus Guard extension closes the sites you reach for when bored, and flags it if you drift to another tab, so the 90 minutes stays whole.

Then take the 15 minute break seriously. Get away from the screen, move your body, let your mind go quiet. This is the trough of the wave, and rest is what lets the next block be sharp instead of foggy.

What GoFlow tracks across your blocks

Each 90 minute block you finish gets logged against the task you named, and your tasks carry across days. GoFlow sums your hours of deep work, tasks worked on, tasks completed, and shows a 7-day bar so you can see how many deep waves you are catching each week. A hard project that took two 90 minute blocks today and one yesterday reads as three real waves of deep work, not a blank timer each morning.

90 minute block vs shorter rounds

Free, private, offline

No sign-up, no paywall, no tracking. Your blocks, tasks, and stats stay on your device, and the timer keeps running with no internet. Install GoFlow to your dock or home screen and start a 90 minute block in one tap.

90 minute focus timer FAQ

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