How Many Seconds in a Day?
There Are
86,400
seconds in one 24-hour day
There are exactly 86,400 seconds in a day. This is true for every standard 24-hour day. The calculation is straightforward: multiply the 24 hours in a day by the 60 minutes in an hour, then multiply by the 60 seconds in a minute.
There Are 86,400 Seconds in a Day
Here is the step-by-step calculation:
1
1 day = 24 hours
2
24 hours × 60 minutes = 1,440 minutes per day
3
1,440 minutes × 60 seconds = 86,400 seconds per day
24 × 60 × 60 = 86,400 seconds
Convert Hours, Minutes & Days to Seconds
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Seconds, Minutes and Hours Conversion Table
Use this quick-reference table to convert common time periods to seconds:
| Time Period | Days | Hours | Minutes | Seconds |
|---|---|---|---|---|
| 1 minute | 0.000694 | 0.0167 | 1 | 60 |
| 1 hour | 0.0417 | 1 | 60 | 3,600 |
| 6 hours | 0.25 | 6 | 360 | 21,600 |
| 12 hours (half day) | 0.5 | 12 | 720 | 43,200 |
| 1 day (24 hours) | 1 | 24 | 1,440 | 86,400 |
| 2 days | 2 | 48 | 2,880 | 172,800 |
| 3 days | 3 | 72 | 4,320 | 259,200 |
| 1 week (7 days) | 7 | 168 | 10,080 | 604,800 |
| 2 weeks | 14 | 336 | 20,160 | 1,209,600 |
| 30 days | 30 | 720 | 43,200 | 2,592,000 |
| 1 year (365 days) | 365 | 8,760 | 525,600 | 31,536,000 |
Other Common Time Conversions
3,600
Seconds in one hour
1,440
Minutes in one day
86,400,000
Milliseconds in a day
604,800
Seconds in one week
2,592,000
Seconds in 30 days
31,536,000
Seconds in one year (365 days)
Frequently Asked Questions
How many seconds are in a 24-hour day? ＋
There are exactly 86,400 seconds in a standard 24-hour day. This is calculated as 24 hours × 60 minutes × 60 seconds = 86,400 seconds.
How many seconds are in half a day? ＋
There are 43,200 seconds in half a day (12 hours). That is 12 × 60 × 60 = 43,200 seconds.
How many milliseconds are in a day? ＋
There are 86,400,000 milliseconds in a day. Since 1 second = 1,000 milliseconds, multiply 86,400 × 1,000 = 86,400,000 milliseconds.
How do you convert hours to seconds? ＋
To convert hours to seconds, multiply the number of hours by 3,600 (since there are 3,600 seconds in one hour). For example, 5 hours = 5 × 3,600 = 18,000 seconds.
How many seconds in a week? ＋
There are 604,800 seconds in a week. That is 7 days × 86,400 seconds per day = 604,800 seconds.
How many seconds in a year? ＋
There are 31,536,000 seconds in a standard 365-day year. In a leap year (366 days) there are 31,622,400 seconds.