90 Minute Timer
A 90:00 countdown, already dialed in — press Start and get a triple beep plus a flashing display when time is up. Free, no sign-up, and the tab title keeps counting even while you work in another tab.
Minutes
Custom minutes
Custom seconds
Timer
90:00
Pick a preset or set a custom time, then press Start.
A beep plays when the timer finishes — keep this tab's sound on.
What a 90 minute timer is good for
Ninety minutes matches one full sleep cycle (which is why 90-minute naps leave you clear-headed), the ultradian rhythm many people use for deep-work blocks, and a soccer match without stoppage time.
Need a different length? Change the minutes right in the timer above, or jump to another preset below. For counting up instead of down, use the Online Stopwatch; for counting down to a calendar date, try the Countdown to Date.