90 minute pomodoro for a deep block
A 90 minute pomodoro is one deep block, not four short ones. Ninety minutes of focus, twenty minutes off, and a thirty minute pause after every second block.
Pomodoro Timer · Other pages: 50/10 · 52/17
A ninety minute block on the spare screen
Ninety minutes is long enough that a timer in the corner of a laptop gets ignored, and then sudden. A large countdown on a second screen stays in peripheral vision for the whole block. The digits include the hour, so the layout does not jump when the clock passes an hour. Use it for a chapter, a rehearsal, or a piece of work that falls apart if you stop at minute twenty. The short break is twenty minutes, which is a real stop: leave the desk. After two blocks, the long break is thirty minutes. Two nineties is a serious morning, and the pause between them is the point. Keep the device awake. An hour and a half is long enough for a laptop to sleep and take the chime with it, so set the system sleep longer than the block, or use an iPad with Auto-Lock set to Never. Name the task in settings if more than one person can see the screen. Skip is there if the block is done early. It does not add to today's count. The plain timer is the better tool when you want ninety minutes once and no second phase.
FAQ
Will the digits stay the same size for the whole ninety minutes?
Yes. At an hour or more the display includes the hour from the start, so the type does not resize when you cross from 1:30:00 into the fifties. Dim the screen if it will sit at full brightness for that long. Burn-in shift can nudge the layout a few pixels on a panel you leave on often.
Is ninety minutes too long for one sitting?
For some work, yes. Use it when the task has a slow start and a long middle, and take the twenty minute break when it ends. If you already know you want to stop sooner, the 50 minute page is the nearer length. Do not renegotiate at minute seventy. That is what the digits are for.