How Many Seconds Are in a Day?

There are 86,400 seconds in a day. This comes from multiplying the units of time in a standard 24-hour day:

• 60 seconds in a minute
• 60 minutes in an hour
• 24 hours in a day

So the math is: 60 × 60 × 24 = 86,400 seconds.

For quick reference, here are related time conversions:

• 1 hour = 3,600 seconds
• 1 week = 604,800 seconds
• 1 (365-day) year = 31,536,000 seconds

Note that this assumes a standard solar day. On rare occasions, a "leap second" is added to keep atomic clocks aligned with Earth's slightly irregular rotation, making that specific day 86,401 seconds long.