Classroom timer

So much of class runs on time limits: five minutes of independent work, ten minutes in groups, two minutes to talk it over with a partner. When the time is up on the board, students pace themselves better and stop asking how long is left. This classroom timer is built for the projector: big, readable from across the room and clear at a glance.

Teachers use it for:

• Independent work and quizzes: students can see exactly how much time they have.
• Group work and stations: the bell signals the rotation.
• Presentations: everyone gets the same time, and the light shows when to wrap up.
• Transitions and clean-up: "two minutes, then everyone's in their seat."

There's also a timer inside the Random student picker, next to the name picker. This page is the stand-alone, full screen version.

Choose from three displays, each suited to different ages and situations:

• Traffic light: green for the first half of the time, amber from 50% to 20% left, and red for the last 20%. It's the easiest for younger students, because nobody needs to read a clock.
• Shrinking ring: the ring changes color the same way and shows how much time has gone. It's great for proportions: "we're halfway there."
• Digits and bar: huge minutes and seconds with a colored bar underneath. The most precise view for older students and tests.

A dark background has more contrast on a projector; a light one can work better in a bright room. You can add your own title, like "Group work" or "Silent reading", and it stays on screen in full screen mode.

During class there's no time to hunt for the mouse, so everything works from the keyboard:

Key	What it does
Space or Enter	Start / pause
R	Reset
+	Add a minute
F	Full screen
Esc	Exit full screen

The timer follows the real clock, not animation frames, so it stays accurate even if you switch to another window or your slides. When time is up, a bell rings (you can turn it off) and the display flashes red a few times, unless your device is set to reduce motion.

Some starting points that work in many classrooms:

Activity	Suggested time
Turn and talk with a partner	1–2 min
Bell ringer or warm-up	3–5 min
Independent worksheet	8–12 min
Group work at a station	6–10 min
Student presentation	3–5 min
End-of-class clean-up	2 min

Younger students usually do better with shorter, more frequent blocks; older students can handle longer stretches of independent work. If none of the quick buttons fits, type your own, like 7:30.

• Say what happens at the bell: pens down, or just signal that you're done? Clear expectations stop the bargaining.
• Shorter blocks work better. Two 10-minute blocks with a quick check-in often beat one 20-minute stretch.
• Build in a buffer. The + button adds a minute when you can see most groups are nearly done.
• Use the light for younger kids. Amber is a great cue to finish the sentence and start tidying up.

The timer runs in your browser, there's nothing to install and there's no daily limit. Your time, display and sound settings are saved in this browser, so you can pick up where you left off tomorrow.