Any specific time period that is utilized as a standard manner of measuring or expressing duration is referred to as a unit of time. The second is the basic unit of time in the International System of Units (SI) and, by extension, much of the Western world. It is defined as about 9 billion oscillations of the cesium atom.

The history of measurement is very interesting and very rich. Many units of time have been determined historically by the motions of celestial objects.

The year was named after the year in which the Earth revolved around the Sun. The Olympiad (four years), the lustrum (five years), the indiction (15 years), the decade, the century, and the millennium are all historical year-based units.

The month was determined by the orbital period of the Moon around the Earth.

Earth-based: period of time it took for the Earth to spin on its own axis, as measured by a sundial. The week (seven days) and the fortnight were originally formed from this basis (14 days). The day was split into hours (1/24 of a day), minutes, and, lastly, seconds. The second became fundamental quantity in the scientific international standard unit

(SI units).

If you want learn something new, this is right place to be, and learn more about time conversion calculator. Also, there is another time related calculator, and that is Time to Decimal Calculator.

How to use the time unit converter

Simply enter the number you want to convert to a field with the appropriate unit to convert between time units. Just look for the unit you are interested in, and the time unit converter will calculate the value in all other units. With this method, you can convert milliseconds to minutes, determine how many days there are in two years, and so on. If you prefer an alternative unit layout, you can change it by selecting the ones you want from the drop-down menu (access it by clicking on the unit itself) in any field.

How the time unit converter works

A year is equal to 365.25 days in our time unit calculator. This is a rough estimate of a sidereal year, which is the length of time it takes the Earth to orbit the Sun – on average 365.256363004 days:

(365 days 6 hours 9 minutes 9.76 seconds).

A year is 12 months and a week is seven days in the Gregorian calendar, which is used by the majority of the globe. A day is traditionally 24 hours long, an hour is 60 minutes long, a minute is 60 seconds long, and a millisecond is 1/1000 of a second long.

All of the relationships between the units utilized in the time unit converter may be deduced from these assumptions. Let’s summarize:

1 y= 365.25 d
1 w= 7 d
1 d= 24 h
1 h= 60 min
1 min= 60 s
1 s = 1000 ms= 1000 ms
The relationships between the units


  • y – year
  • w – week
  • d -day
  • h – hour
  • min – minute
  • s – second
  • ms – millisecond.

How to Convert Units of Time

If you want to know how conversion of units works to convert units of time, firstly you have to know these significant figures:

  1. 60 seconds = 1 minute
  2. 60 minutes = 1 hour
  3. 24 hours = 1 day
  4. 7 days = 1 week
  5. 12 months = 1 year
  6. 52 weeks = 1 year
  7. 365 days = 1 year (366 for leap years)
  8. 10 years = 1 decade
  9. 100 years = 1 century
  10. 1000 years = 1 millennium

Here we have two very simple conversion factors. These factors are:

  • if you take a larger unit and want to turn it into a smaller one then you have to multiply;
  • if you want a smaller unit to turn into a larger one then divide.

We will give a few examples, to make it clearer to you.


Example 1

How many hours are in 7 days?

We’d want to convert seven days to hours. Days are longer than hours, and we must multiply since we are going from huge to little.

Here we are using multiplication, so we multiply the numbers 7 and 24 because we have 24 hours a day.

7 x 24 = 168

So, that means there are 168 hours in 7 days.

Example 2

If your dad is alive for 50 years. How many decades is that?

We’ll need to divide 50 years into decades. We’re going from little to huge since years are smaller than decades. That implies we’ll have to divide.

We’ll divide by ten because there are ten years in a decade.

50 ÷ 10 = 5

That means that your dad is alive for 5 decades.

Example 3

How many seconds are in 5 hours?

The conversion will be done in two steps:

Convert hours to minutes, minutes to seconds, and seconds to minutes.

To convert 5 hours to minutes, we must first recognize that we are moving from a huge to a little number, hence we must multiply.

We’ll multiply by 60 because there are 60 minutes in an hour.

5 x 60 = 300

There are 300 minutes in 5 hours.

We must now translate 300 minutes into seconds.

We’ll increase that by 60 because there are 60 seconds in a minute.

300 x 60 = 18.000

There are 18.000 seconds in 5 hours.

Complete list of time units for conversion

Megasecond (ms)
Gigasecond (gs)Terasecond (ts)Galactic year (gy)Exasecond (es)Zettasecond (zs)Yottasecond (ys)Fortnight (4tnite)Kilosecond (ks)Nanosecond (ns)Microsecond (µs)Millennium (ky)Century (c)Decade (decade)Year (y)Month (mth)Week (wk)Day (d)Hour (hrs)Minute (mins)Millisecond (ms)Second (s)
1 Megasecond
1 Gigasecond
1 Terasecond
1 Galactic year
1 Exasecond
1 Zettasecond
1 Yottasecond
1 Fortnight
1 Kilosecond
1 Nanosecond
1 Microsecond
1 Millennium
1 Century
1 Decade
1 Year
1 Month
1 Week
1 Day
1 Hour
1 Minute
1 Millisecond
1 Second
This table shows the most common time units being converted to each other

Units, symbols, and conversion values used in this time calculator

To Convert from UnitUnit Symboland Convert to ( s )Multiply by ( s / Unit )
second (sidereal)sSecond0.99726956
minute (sidereal)minSecond59.83617361
hour    hSecond3600
hour (sidereal)hSecond3590.170417
day (sidereal)dSecond86164.09
year (sidereal) yrSecond31449892.85
Table of units, symbols, and conversion values used in this time calculator

In this table you have all the units, symbols, and conversion values used in this time calculator. Everything is in one place, so you can easily find the information you need.

Time Unit Conversion Table

1 hour60 minutes 
1 minute60 seconds 
1 hour60 minutes3600 seconds
1 day24 hours 
1 week7 days 
1 year365 days 
1 year12 months 
1 year52 weeks 
Conversion table of time units

How to convert between units of time – from hours to minutes, from years to seconds

What did people do when they didn’t have access to this handy time converter? Let’s have a look at how you may go about converting between time units on your own.

If you wish to convert from a “larger unit” to a “smaller unit,” you must first go through all of the “in-between” units. If you wanted to know how many seconds are in a week, you might use the following formula:

  • So far, we have explained to you in a very simple way, and also in a pictorial way how the conversion unit is performed. But how do we turn hours into minutes? Or years in seconds after all? Keep reading. So, we have learned so far and we know that one day consists of 24 hours. In the table below you have the necessary data for the given task:
Table of formulas that you need to know
  • Replace d with 24 hours, h with 60 minutes, and so on until the appropriate unit is reached:

1 w = 7 x 24 x 60 x 60 s

1 w = 604,800 s

  • We arrived at the following conclusion, converted result: one week equals 604,800 seconds.

Solved Examples on Converting Days into Hours and Hours into Minutes

 Hours into minutes:

  1. Convert 5 hours into minutes.

We know, 1 hour is 60 minutes

So that means,

5 hours = (5 × 60) minutes = 300 minutes

  •  Convert 18 hours into minutes.

We know, 1 hour is 60 minutes

So that means,

6 hours = (18 × 60) minutes = 1080 minutes

  • Convert 9 hours 35 minutes into minutes.

First, we convert 9 hours into minutes and then we add 30 minutes to it.

9 hours 35 minutes = (9 × 60) minutes + 35 minutes (1 hour = 60 minutes) = 540 minutes + 30 minutes = 570 minutes.

Days into hours:

It is also very easy, just follow this formula:

 day x 24 = hours


  1. How many hours is in 4 days?

4 x 24 = 96

In 4 days, there are 96 hours.

  • How many hours is in 15 days?

15 x 24 = 360

In 14 days, there are 360 hours.

  • How many hours is in 34 days?

34 x 24 = 816

In 34 days, there are 816 hours.