The Pomodoro technique with ADHD: how long should a block be?

The Pomodoro technique is the first thing most people with ADHD are told to try, and the first thing many of them abandon. The complaint is nearly always the same: twenty-five minutes is either a wall they cannot get over or an alarm that goes off just as they finally got going. Both are real, and neither means the method is wrong for you. It usually means the number is. This article is about choosing the number, and about the few rules that matter more than it.

Why a timer helps at all

One influential model of ADHD, set out by Russell Barkley in 1997, describes it less as a shortage of attention and more as difficulty holding the future in mind: the deadline, the end of the task, the passing of time itself. People often call this time blindness. A visible countdown is an attempt to put that missing information outside your head, where you can see it. "Work until it is done" has no edge; "work until the chime" does.

The honest caveat is that nobody has run a proper trial of the Pomodoro technique in adults with ADHD. The nearest evidence comes from ordinary students. A 2023 study compared fixed, Pomodoro-style breaks with breaks taken whenever students felt like it, and the fixed schedule went with less reported fatigue and similar amounts of work done. That is one study, self-reported, with no ADHD focus. It suggests structure is not a cost; it does not prove a timer will fix anything.

The two ways 25 minutes goes wrong

Too long to start. On a bad day the hard part is not minute twenty; it is minute zero. Twenty-five minutes of a task you are dreading can feel like an afternoon, so you do not press start. The fix is to make the first block smaller than your resistance: ten minutes, with explicit permission to stop when it ends. Most people do not stop, because starting was the problem and it is already solved.

Too short once you are in. Many adults with ADHD describe hyperfocus, long stretches of total absorption in one thing. A 2019 questionnaire study found that adults with more ADHD symptoms reported more of it, though it is self-report and the concept is still loosely defined. If you have spent forty minutes getting into a problem, an alarm at twenty-five is not a gift. Rebuilding that context after a break can take longer than the break.

Find your length in a week

The right length is personal and it changes with the task, so test it rather than adopt it. A simple version:

1. Days one and two: 25 minutes on, 5 off. After each block, write two numbers: how many times you drifted, and whether the chime came too early, about right, or too late.
2. If the chime keeps coming too early, move up to 50 minutes with a 10-minute break, or 52/17 if you also find five-minute breaks too short to actually rest.
3. If you keep not starting, go down: a ten-minute first block with a kitchen timer, then a normal 25-minute block once you are moving.
4. For work you already know well, such as a long writing session on a chapter you have planned, try a 90-minute block. It is a poor choice for anything new or boring.
5. Day seven: look at the numbers. Pick a default for each kind of task, not one length for everything.

Many people end up with two lengths: a short one for starting and for dull admin, a long one for the work they care about. That is not cheating the method. It is the method fitted to you.

Rules that matter more than the number

• Write the task before you press start. One line: "draft the intro", not "work on report". A block without a target turns into tidying.
• The break needs an end too. For a lot of people with ADHD the break, not the block, is where the afternoon disappears. A five-minute break on a phone is rarely five minutes. Stand up, get water, come back to a timer that is waiting for you.
• The phone goes in another room. A 2017 study by Ward and colleagues found people did worse on memory tests with their phone on the desk than in another room; a 2022 replication found a much smaller effect. Whatever the size, a phone you cannot reach cannot start a break for you. More in why your focus timer should not be on your phone.
• Cover the room. Steady sound such as brown noise or rain masks voices, which is well established. Whether noise helps ADHD attention in a deeper way is less clear: Söderlund's stochastic resonance studies found a benefit, but they were small, mostly in children, and replications have been mixed. Worth testing, not worth believing. The details are in the best background noise for ADHD focus.

Where Kiri fits

The timer above is the one this article describes. It has the four lengths from the test, 25/5, 50/10, 52/17 and 90, a line for the task, a countdown in the tab title and a chime at the end, and after a break the next block starts only if the Kiri tab is in front of you; if you have wandered off, it waits. It runs on a laptop and refuses to run on a phone, on purpose. It is free to use with rain and brown noise; the full version adds eight more soundscapes, all long, non-looping blends of real field recordings, for a one-time €39 with no subscription. Kiri does not have a ten-minute block, so for that first small start a kitchen timer is perfect. If the hardest part for you is starting alone, body doubling when you work alone covers that.