90 Second Timer
A ready-to-go 01:30 countdown -- press Start, or set a different duration below if you need one.
Keyboard: Space start/pause, R reset, Esc stop alarm.
What a 90 second timer is used for
- the standard pitch length used by many startup accelerators and demo-day formats
- a common plank-hold endurance benchmark once someone has passed the one-minute mark
- a full steep time for many green teas
- a short countdown for a young kid's waiting-room patience
- a solid warm-up interval before a harder work set
Why 90 seconds
Ninety seconds is a specific, real standard in the startup world -- many accelerators and demo days cap an initial pitch at exactly ninety seconds, forcing founders to compress their whole idea into a tight, rehearsed window -- and it's also a common next benchmark once someone's built past a one-minute plank hold.
90 seconds = 1.5 minutes = 1/40 hour
How it stays accurate
Like every timer on this site, this one never counts down by subtracting one second at a time -- it records the exact target end timestamp the moment you press Start, then recomputes the time left from that fixed target on every screen update. Switching tabs, minimizing the window, or letting the browser throttle a background tab doesn't cost any accuracy, because the next update still does the subtraction fresh rather than trying to catch up on missed ticks. The alarm itself is synthesized with the Web Audio API -- no audio file, nothing an ad blocker could interfere with -- and repeats until you stop it with the Escape key, the Stop alarm button, or by starting a new countdown.
Frequently Asked Questions
What is a 90 second timer good for?
A few common uses: the standard pitch length used by many startup accelerators and demo-day formats; a common plank-hold endurance benchmark once someone has passed the one-minute mark; a full steep time for many green teas.
How long is 90 seconds in other units?
90 seconds = 1.5 minutes = 1/40 hour.
Does this 90 second timer stay accurate if I switch tabs?
Yes -- it stores the exact moment the countdown should end and recomputes the time left from that fixed target on every update, rather than counting ticks, so a background tab that gets throttled for a while doesn't cost any accuracy.
Why is 90 seconds a notable duration?
Ninety seconds is a specific, real standard in the startup world -- many accelerators and demo days cap an initial pitch at exactly ninety seconds, forcing founders to compress their whole idea into a tight, rehearsed window -- and it's also a common next benchmark once someone's built past a one-minute plank hold.