Classic 25
A Pomodoro timer, and what comes after it.
You came looking for a Pomodoro timer. Particle has one — 25 minutes, one task, one keystroke, in your browser. It also knows what the research says about where 25 minutes came from, and what to do when it stops being enough.
Free. No account. No download. No ads.
What the tomato got right
In 1987, a university student named Francesco Cirillo picked up a tomato-shaped kitchen timer, set it for 25 minutes, and made himself a deal: pure focus, nothing else. Four decades later, the Pomodoro Technique is the most widely adopted focus method in the world.
It earned that. The technique gets three things deeply right: one task at a time. A clear boundary around the work. A real break when the boundary closes. Most people who struggle to focus aren't missing willpower — they're missing exactly that structure.
So Particle keeps the tomato. Classic 25 is the first of our three rhythms — one keystroke, and the next 25 minutes belong to one task.
A quieter kind of timer
Most Pomodoro timers tick down. Particle counts up. A countdown manufactures urgency — and research shows that kind of time pressure suppresses creative thinking, with a hangover that outlasts the session. Watching time grow feels different from watching it drain.
There are no streaks to protect, no red badges, nothing that dies when life interrupts you. Stop at minute nineteen, and those nineteen minutes still count. Every finished session becomes a particle — a quiet point in the record of your work that only ever grows.
Black screen. One task. Generative sound if you want it, silence if you don't. The whole thing works from the keyboard, in your browser, without an account.
When 25 minutes stops fitting
Here is the honest part. The 25-minute interval was never science — it was one student's preference, from one kitchen timer, in 1987. The research that has accumulated since points somewhere else: complex work takes 10 to 15 minutes just to enter, which means a Pomodoro can end right as your brain finally arrives.
In 2014, DeskTime analyzed its most productive users and found they worked in blocks of 52 minutes with 17-minute breaks. Sleep researcher Nathaniel Kleitman found the deeper pattern decades earlier: your alertness moves in roughly 90-minute waves, all day long. Elite performers across fields converge on the same shape — longer blocks, real breaks, three or four per day.
That is why Particle ships three rhythms instead of one: Classic 25, Deep Work 52, and a 90-minute block. Start with the tomato. When it starts feeling short — and for deep work, it usually does — the next rhythm is one keystroke away.
Questions
Is this Pomodoro timer really free?
Yes. The timer runs in your browser with no download, no account, and no credit card. Particle’s free tier is free forever — it is designed to be genuinely useful, not a teaser.
Do I need to sign up?
No. Open the app and press one key — the timer works without an account. An account only becomes useful when you want your focus history to follow you across devices.
Why does the timer count up instead of down?
A countdown manufactures time pressure, and time pressure measurably suppresses the kind of thinking deep work needs. Counting up turns the same 25 minutes into something you collect rather than something that drains. When the rhythm completes, you’ll know.
What if 25 minutes feels too short?
That is not a failure — it is usually your biology asking for a longer block. Particle ships three rhythms: Classic 25, Deep Work 52, and a 90-minute block that matches your brain’s natural ultradian cycle. Switching takes one keystroke.
The full thinking
The timer is the doorway.
The work is the room.