Is this timer fixed at exactly 4 hours?

It starts at 4 hours (240 minutes) by default, but you can nudge the length up or down in 15-minute steps, or pick a preset, before clicking Start.

What do the preset buttons do?

Shift, Study Block, Slow Cook, and Road Trip each set a length suited to that use: Shift and Slow Cook use the full 4 hours, Study Block sets 3 hours 30 minutes so you can add a break, and Road Trip sets 4 hours 30 minutes for a rest stop buffer.

Will it make a sound when time is up?

Yes, it plays a short beep through the Web Audio API and flashes the screen red. Make sure your device volume is on to hear it.

How do I show it full-screen?

Click "Fullscreen" for a large display that works well projected on a wall or shared in a video call. Press "Exit Fullscreen" or Esc to return to the normal view.

Can I pause and resume the countdown?

Yes. Click "Pause" while it is running, then click the button again to resume from the exact time remaining.

Does the timer stay accurate if I switch tabs or close my laptop?

It keeps counting in the background, but browsers throttle inactive tabs and sleeping devices, so the alert can land late over a 4 hour span. Keep the tab open and the device awake for the most precise timing.

Does this send any data to a server?

No. The countdown runs entirely in your browser. Nothing about your session is collected or transmitted.

4 Hour Timer

Name: 4 Hour Timer
Availability: InStock
Author: Nham Vu

Start a 4 hour countdown, nudge the length up or down, or jump to a shift, study, cooking, or road trip preset.

4 Hour Countdown

240:00

Presets

Summary

Start a 4 hour countdown, nudge the length up or down, or jump to a shift, study, cooking, or road trip preset.

How it works

Click "Start" to begin the 4 hour countdown, or pick a preset button first to change the length.
Use the "-15m" and "+15m" buttons to fine-tune the length before starting.
Watch the ring shrink and the clock count down toward zero.
Click "Fullscreen" to display a large countdown for a room or stream.
Hear a beep and see the screen flash red when the countdown reaches zero.
Click "Pause" to stop the countdown and "Resume" to pick up where you left off.
Click "Reset" to set the timer back to its last configured length.

Use cases

Time a 4 hour work shift or on-call window.
Cap a study block or exam sitting at 4 hours.
Time a slow-cooker or braise that runs on the low setting.
Keep a road trip driving leg or rest stop on schedule.
Bound a moving, packing, or cleaning session before a deadline.
Time a 4 hour flight, ferry, or layover.
Limit a gaming or screen time session to 4 hours.
Cue a shift change or break rotation at work.

Frequently Asked Questions

Last updated: 2026-07-21 · Reviewed by Nham Vu