8 Hour Timer

A 8 hour (28,800 second) countdown is ready. Press "Start" — an alarm sounds when time is up, and the end time is shown on screen.

08:00:00

Presets

Sound

Set the time

What can you do in 8 hours?

  • A full workday
  • A night's sleep
  • Drying or fermenting

8 Hours in other units

Seconds28,800
Minutes480
Hours8
Milliseconds28,800,000

When will it end?

The timer shows its end time as soon as you press start. Some examples of when 8 hours runs out:

StartEnds at
09:0017:00
12:3020:30
18:0002:00 (next day)
22:4506:45 (next day)

What happens in that time?

Walking (3 mph)24 mi
Running (6 mph)48 mi
Heartbeats (70 per minute)about 33,600
Distance light travels5,364.93 million mi
Share of a day33.33%

Based on typical averages; individual values vary.

For any other length, use the main online timer, or convert time units with the time converter.

Frequently Asked Questions

How many seconds are in 8 hours?
8 hours = 28,800 seconds = 480 minutes = 8 hours.

Does the 8 hour timer keep running in the background?
Yes. It follows the real clock, so it ends on time even if you switch tabs. Just keep the tab open; on phones use "Keep screen awake".

Can I use my own music as the alarm sound?
Yes. Choose "Your own sound" in the sound menu and pick an audio file from your device. It's stored only in this browser and never uploaded.