Convert hours to seconds instantly. Enter a value below, or use the formula and reference table further down the page.
In practice
Hours to seconds multiplies by 3,600, because an hour holds 60 minutes of 60 seconds each. It is the conversion used in physics, programming and speed calculations: 1 hour is 3,600 s, a day is 86,400 s and a year is about 31.5 million seconds. It is also the reason for the 3.6 factor when converting between km/h and m/s. For timers and code, use seconds as the base unit to avoid errors from minutes and hours.
How to convert hours to seconds
Multiply the value by 3600.
s = h × 3600Example: 10 h = 36000 s.
Hours to Seconds conversion table
| Hours (h) | Seconds (s) |
|---|---|
| 1 h | 3600 s |
| 2 h | 7200 s |
| 3 h | 10800 s |
| 4 h | 14400 s |
| 5 h | 18000 s |
| 10 h | 36000 s |
| 15 h | 54000 s |
| 20 h | 72000 s |
| 25 h | 90000 s |
| 50 h | 180000 s |
| 100 h | 360000 s |
Frequently asked questions
How many seconds is 1 hour?
1 hour equals 3600 seconds.
What is the formula to convert h to s?
To convert h to s, multiply the value by 3600. The full formula is: s = h × 3600.
How do I convert seconds back to hours?
Use the same calculator above and type your value into the seconds field instead — it converts in both directions. Or use the reverse formula: h = s ÷ 3600.
Is the h to s conversion exact?
The conversion factor used here (3600) is the standard internationally defined value. Results on this page are rounded to four decimal places for readability.