# Hours to Seconds Converter

URL: https://speedycalculator.com/calculators/conversion/hours-to-seconds-converter/
Last updated: 2026-10-25

> Convert hours (h) to seconds (s): 1 hour = 3,600 s, so multiply by 3,600 or divide by 0.00027777778. Both fields are editable, so you can also type in seconds and get hours back.

## Inputs

- Hours (h)

## Results

- Seconds

## Formula

```
1 h = 3,600 s
1 s = 0.00027777778 h
s = h × 3,600
```

## Explanation

An hour has 3,600 seconds. Physics problems and computer timers often need durations in seconds.

### How to use the Hours to Seconds Converter

- Type the number of hours into the **Hours** field. Decimals such as 0.5 are fine.
- Read the answer in **Seconds** – it updates as you type, with no button to press.
- To convert the other way, type into **Seconds** and the hours are recalculated.
- Press **Copy results** to copy both values with the page title, or **Copy link** to share this exact conversion.

This page converts only h ⇄ s. Need a different unit? Use the general time converter, where you can choose any “from” and “to” unit.

### How it works

Both units measure time, so they are always in the same ratio: one hour equals 3,600 seconds. The calculator multiplies the number of hours you type by 3,600 to give seconds, and when you type into the seconds field it divides by the same factor to give hours. Because the ratio never changes, doubling the hours always doubles the seconds. Results are calculated at full precision and rounded only for display (up to eight decimal places, with very large or small values shown in scientific notation).

### How to convert hours to seconds

- Write down the value in hours, for example **1 h**.
- Multiply by the conversion factor 3,600 (because 1 hour = 3,600 s).
- 1 × 3,600 = **3,600 s**.
- To go back from seconds to hours, divide by 3,600 – or multiply by 0.00027777778.

### h to s conversion table

HoursSecondsSecondsHours0.1 h360 s1 s0.00027777778 h0.25 h900 s2 s0.00055555556 h0.5 h1,800 s5 s0.0013888889 h1 h3,600 s10 s0.0027777778 h2 h7,200 s20 s0.0055555556 h5 h18,000 s50 s0.013888889 h10 h36,000 s100 s0.027777778 h24 h86,400 s1,000 s0.27777778 h

### What is an hour?

An hour is 60 minutes or 3,600 seconds. Wages, shifts and travel times are counted in hours.

### What is a second?

The second is the SI base unit of time, defined by 9,192,631,770 cycles of radiation from a caesium-133 atom.

### Common mistakes to avoid

Treating every month as 30 days or every year as 365 days in long calculations, and writing decimal hours such as 1.5 h as 1 h 50 min (it is 1 h 30 min).

## Worked example

Inputs — Hours: 1 h.

Results — **Seconds = 3,600 s**.

## FAQ

**How many seconds in an hour?**
3,600.

**How many seconds in a day?**
86,400.

**How do I convert hours to seconds?**
Multiply the number of hours by 3,600. For example, 1 h × 3,600 = 3,600 s.

**How do I convert seconds back to hours?**
Divide by 3,600 (or multiply by 0.00027777778), or simply type the value into the seconds field above.

**What is 10 h in seconds?**
10 h = 36,000 s.

**What is 5 h in seconds?**
5 h = 18,000 s.

**Is this conversion exact?**
Yes. The factor comes from the official definitions of both units (NIST and the SI), so the only difference you may see is rounding in the last displayed digit.

**Can I convert to other units on this page?**
This page converts only between hours and seconds. To pick any time unit, use the general time converter linked under Related calculators.

**What formula does the Hours to Seconds Converter use?**
1 h = 3,600 s.


## Sources

- [NIST Special Publication 811 – Guide for the Use of the International System of Units](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44 Appendix C – General tables of units of measurement](https://www.nist.gov/pml/owm/nist-handbook-44-current-edition)