There are 3,600 seconds in 1 hour, because 1 hour = 60 minutes and 1 minute = 60 seconds, so 60 × 60 = 3,600. To convert hours to seconds, multiply by 3,600: 2 hours = 7,200 seconds and 2.5 hours = 9,000 seconds. To convert seconds to hours, divide by 3,600: 5,400 seconds = 1.5 hours.
Reviewed by the Helping with Math Team · Updated 10 October 2026
Hours to seconds chart
- 1 hour = 3,600 seconds
- 2 hours = 7,200 seconds
- 3 hours = 10,800 seconds
- 4 hours = 14,400 seconds
- 5 hours = 18,000 seconds
- 6 hours = 21,600 seconds
- 8 hours = 28,800 seconds
- 10 hours = 36,000 seconds
- 12 hours = 43,200 seconds
- 24 hours (1 day) = 86,400 seconds
- ½ hour = 1,800 seconds, ¼ hour = 900 seconds
Seconds = hours × 3,600. Hours = seconds ÷ 3,600.
Units of time: hours, minutes and seconds
Time tells us how long something lasts or when it happens. We measure time in seconds, minutes, hours, days, weeks, months and years with clocks and calendars. We can observe that there are 12 numbers written on the face of a clock. We also know that a day has 24 hours. Therefore, the hour hand of the clock completes 1 round in 12 hours. So, we divide 24 hours of a day in two periods:
- From 12:00 midnight to 12:00 noon
- From 12:00 noon to 12:00 midnight
The time between 12:00 midnight to 12:00 noon is written as a.m. Here a.m. means ante meridiem which means before midday.
The time between 12:00 noon and 12:00 midnight is known as p.m. Here p.m. means post meridiem which means after midday.
Another thing that should be noticed is that at times we see time written in a.m. or p.m. while at times it is written as, say, 16:00 with no mention of a.m. and p.m.
How to convert hours to seconds
Time is measured in hours, minutes and seconds. How are these three related to each other?
1 minute = 60 seconds
1 hour = 60 minutes
This means that 1 hour = 60 x 60 = 3600 seconds
Therefore, to convert hours into seconds, we will have to multiply the value of hours by 3600. Let us understand it through an example.
Example
How many seconds are there in 2 hours?
Solution
We need to convert 2 hours into seconds.
Now, we know that 1 hour = 3600 seconds
So, 2 hours = 2 x 3600 = 7200 seconds
So, there are 7200 seconds in 2 hours
It is important to understand that a second is a very short period of time, say the time that is taken to blink your eye, to snap your fingers etc. it is a smaller unit of time than a minute.
To understand how to convert hours into seconds, let us consider another example.
Suppose Victor and his sister Alice were going to school. When they started from home, the following time was shown by the clock –
Victor asked her to read the time. She read it easily as 7:30. Then they reached the school and the time shown by the clock in the school is
Victor again asked her to read the time. But, she was not able to read the time to the exact minutes. Now, Victor told her it was 8: 10. Let us understand how to read time to exact minutes.
If you see carefully, there are 12 numbers and 60 divisions on the face of a clock. Therefore, we have,
1 hour = 60 minutes.
Hence, the number of divisions between two consecutive numbers is 60 ÷ 12 = 5 divisions or 5 minutes.
We will read the time on the given clock as 2 :07 if,
- The hour hand of the clock is at 2
- The minute hand of the clock is at the 2nd division after the 1st number, i..e 7 minutes ( 1 x 5 = 5) + 2 minutes = 7 minutes.
Hence, we can say that the numbers on the clock actually represent hours and the divisions between them represent the minutes.
It is important to know here that –
Quarter of an hour = 60 ÷ 4 = 15 minutes = 15 x 60 = 900 seconds
Half of an hour = 60 ÷ 2 = 30 minutes = 30 x 60 = 1800 seconds
12 :00 o’clock in the night is 12:00 midnight
12 :00 o’clock at the daytime is 12:00 noon
We do not write a.m. or p.m. with 12:00 o’clock time.
In what time do the hour, minute and second hands complete one round or one revolution of the clock?
- The hour hand of the clock goes round the clock in 12 hours.
- The minute hand completes one round in 1 hour.
- The second’s hand completes one round in 1 minute
Now, what if we want to convert seconds into hours?
How to convert seconds to hours
We know that 1 hour = 3600 seconds. This means that
1 second = $\frac{1}{3600}$ hours
From above, we can see that in order to convert seconds into hours, we will have to divide by 3600
Let us understand it through an example.
Example
Convert 5400 seconds into hours
Solution
We know that 1 second = $\frac{1}{3600}$ hours. This means that for converting 5400 seconds into hours we will have to divide 5400 by 3600.
So, 5400 ÷ 3600 = 1.5
Hence, 5400 seconds when converted into hours is 1.5 hours.
Hours to seconds examples
Example 1
Convert 2 hours 35 minutes into seconds
Solution
We are required to convert 2 hours 35 minutes into seconds. Now, we know that
1 hour = 3600 seconds
This means that 2 hours = 2 x 3600 = 7200 seconds . . . . . . . . . . . . . . . . . . . . . . ( 1 )
Also, we know that 1 minute = 60 seconds
Therefore, 35 minutes = 35 x 60 = 2100 seconds
So, 2 hours 35 minutes = 7200 + 2100 = 9300 seconds ( From equation ( 1 ) )
⇒ 2 hours 35 minutes = 9300 seconds
Hence, we can say that 2 hours 35 minutes is equal to 9300 seconds.
Example 2
Alicia’s family is traveling from Atlanta, Georgia to New York by plane. Their flight leaves at 9:15 a.m. and should take 8100 seconds. What time will their plane arrive in New York?
Solution
We have been given that Alicia’s family is traveling from Atlanta, Georgia to New York by plane. Their flight leaves at 9:15 a.m. and should take 8100 seconds. We need to find the time at which their plane arrives at New York.
The first thing that we would do when solving for elapsed time is to figure out our start time and end time. Here, our start time is 9:15 a.m. and the end time is 8100 seconds after the start time.
We know that 1 second = $\frac{1}{60}$ minute
Therefore, 8100 seconds = $\frac{1}{60}$ x 8100 = 135 minutes
Next, we are going to count to the nearest hour after the start time, i.e. 9:15 a.m. Looking at the clock, we know that the next hour after 9:15 a.m. would be 10:15 a.m. So counting from 9:15 a.m. to 10:15 a.m.. we see that there is one hour from 9:15 a.m. and 10:15 a.m. Since we are required to find the time 135 minutes after 9:15 a.m., therefore we shall now jump another 1 hour from 10:15 a.m. Looking at the clock, we know that the next hour after 10:15 a.m. would be 11:15 a.m. So counting from 10:15 a.m. to 11:15 a.m. . We see that there is one hour from 10:15 a.m. and 11:15 a.m.
So, we have now counted 2 hours from 9:15 a.m. and reached at 11:15 a.m. we are left to count 15 minutes now. Looking at the clock again, we can see that 15 minutes after 11:15 a.m. would be 11:30 a.m. So, what would be the time 15 minutes after 11:15 a.m? It would be 11:30 a.m. Hence, the plane would arrive in New York at 11:30 a.m. which is 2 hours and 15 minutes after it left Atlanta.
Summary
- 1 hour = 60 minutes = 3,600 seconds
- 1 minute = 60 seconds
- 1 hour = 60 minutes
- Quarter of an hour = 60 ÷ 4 = 15 minutes
- Half of an hour = 60 ÷ 2 = 30 minutes.
- 1 minute = $\frac{1}{60}$ hours
More practice: world time zones worksheets, converting units of time worksheets and converting units of time: worksheets.
Hours to seconds FAQs
How many seconds are in an hour?
3,600 seconds. An hour has 60 minutes and each minute has 60 seconds, so 60 × 60 = 3,600.
How do you convert hours to seconds?
Multiply the number of hours by 3,600. For example, 3 hours × 3,600 = 10,800 seconds.
How many seconds are in 2 hours?
7,200 seconds (2 × 3,600).
How do you convert seconds to hours?
Divide by 3,600. For example, 9,000 seconds ÷ 3,600 = 2.5 hours, which is 2 hours 30 minutes.
How many seconds are in a day?
86,400 seconds: 24 hours × 3,600 seconds.
How do you convert hours and minutes to seconds?
Convert each part and add. 2 hours 35 minutes = 2 × 3,600 + 35 × 60 = 7,200 + 2,100 = 9,300 seconds.
