100 Minute Timer
Free online 100 minute countdown timer with alarm
Set a 100 minute timer, an hour and forty, for a full match, a long lab session, or a deep work block with the break already built in.
Space start/pause · R reset · +− adjust
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Embed this timer
Paste this into any page — a class blog, a lesson plan, a meeting agenda — and visitors get a working 100 minute timer with no script tag, no account and no tracking. Please keep the credit link.
About the 100 Minute Timer
A 100 minute timer built for long blocks: accurate from an absolute finish time, visible fullscreen across a room, quietly backed by rain or brown noise, and alarming at zero even from a background tab.
TimerHub calculates remaining time from an absolute finish timestamp, so missed browser callbacks do not create drift. Read the timing accuracy methodology and reproducible tests.
Common Uses
- Full sleep cycle nap
- Deep work block
- Exam practice
- Long workout with cooldown
- Lecture or class session
How to Use the 100 Minute Timer
- Click Start (or press Space) to begin your 100 minute countdown
- Press Space again to pause and resume, or R to reset the timer
- Use the +/- buttons to adjust by 1 minute while running
- Toggle Repeat to loop the countdown automatically, and watch the finish time under the display
- Use the Fullscreen control below the timer for a large full-screen countdown (Esc to exit)
- Pick a background sound — rain, ocean, fireplace or brown noise — that fades out at zero
- Choose or mute the alarm sound from the sound settings in the header
- Add
?autostart=1to the link to start the countdown on load - Enable notifications for alerts when your 100 minute timer finishes, even in a background tab
Frequently Asked Questions
How many hours and minutes is 100 minutes?▾
100 minutes is 1 hour 40 minute. This page counts down the full 100 minutes and sounds an alarm at zero, so you do not have to do the conversion twice.
How long is 100 minutes?▾
100 minutes is exactly 6,000 seconds, or 1.7 of an hour. Our free 100-minute timer counts down precisely and alerts you when time is up.
What can I do in 100 minutes?▾
A 100 minute timer is great for full sleep cycle nap, deep work block, exam practice. Set it and focus on your task — the alarm will let you know when time is up.
Does the timer work in the background?▾
Yes, our timer continues running even if you switch to another tab or minimize your browser. Enable notifications to get alerted when it finishes.
Does the alarm sound when the timer finishes?▾
Yes, an alarm plays automatically the moment the 100 minute countdown reaches zero, with an optional vibration on mobile. Enable notifications for an extra system alert, even from a background tab.
Can I make the timer fullscreen?▾
Yes, use the Fullscreen control below the timer to expand the countdown to your whole screen — great for classrooms, presentations, and workouts. Press Esc to exit fullscreen.
Can I use the 100 minute timer on my phone?▾
Yes, our 100 minute timer is fully responsive and works on all devices including iPhone and Android. Open this page in your mobile browser and tap Start.