Thema Time units ﹣ Converter Month to Day

Here you can convert the Time unit Month into the unit Day and vice versa you can convert Day into Month. By clicking the "Swap units" icon, you will always obtain the desired conversion in the calculation result, i.e., mo to d or d to mo. With the following calculator you can also calculate any other Time unit.

## Info about "Month"

A month forms the time span of 28, 29, 30 or 31 consecutive days. Due to its varying length, the month is not a physical unit of time and thus not a unit of time in the international SI system of units.

To enable a general conversion (e.g., into seconds, minutes or years), the average length of the month in days is defined: Since a year comprises 12 months, a normal calendar year with 365 days results in a month length of 365 / 12 = 30.416667 days

In astronomical terms, a month is defined as the period of one complete revolution of the moon. Depending on the definition, the lunar month is a little more than 28 days on average.

## Info about "Day"

Although the day (d) (Latin: dies) is not part of the International SI System of Units, it is indirectly approved for use with the SI through its definition that a day has 24 hours, and it is indirectly permitted for use with the SI. This is because the second form the official SI base value.

Therefore, 1 day equals 24 hours; 1440 minutes = 86,400 seconds 1 second equals 0.0000115741 days.

For thousands of years, the astronomical day (i.e., the time from sunrise to sunrise again) was the historical basic unit of time. The first reliable time measurements were made by the Egyptians in daylight using sundials, which they divided into 12 units according to their usual system of twelve numbers. At night, they used the position of the 12 stars to measure the time at night. It was not yet so important as days were longer in summer than in winter. Basically, the day and night were divided into twelve time periods. It was only 2,000 years ago that Greek astronomers divided the day into hours of equal length.

The day as the basis for time was not replaced by the second until the middle of the 20th century. With the use of modern quartz clocks, it was proven that the astronomical day (i.e., one revolution of the Earth) is constantly becoming somewhat slower. This confirmed the assumption that magma shifts beneath the earth's mantle and also the tides slow down the Earth's rotation. Therefore, since 1956, the second has been defined in such a way that it is measured by an atomic clock and a leap second must be added to the calendar year every 2 to 5 years. Hence, a day that is actually 86,400.003 atomic seconds long is always 86,400 seconds long, and from time to time, it has a one-off of 86,401 seconds.

## Basis for conversion Month (mo) to Day (d) and vice versa

The abbreviation for the "Time unit Month" is mo. The abbreviation for the "Time unit Day" is d.

## Formula for the conversion of Month (mo) to Day (d) and vice versa

The calculation from Month to Day shall be made using the following conversion formula:

Conversion formula Month to Day

Determine the number of Day from Month

Month × 30.416666650899

## Formula for the conversion of Day (d) to Month (mo)

The calculation from Day to Month shall be made using the following conversion formula:

Conversion formula Day to Month

Determine the number of Month from Day

Day × 0.03287671234581

## Overview table : How many Month are in Day ?

Month mo ⇒ Day d
0.01 mo  are  0.30416 d
0.02 mo  are  0.60833 d
0.03 mo  are  0.91250 d
0.04 mo  are  1.21666 d
0.05 mo  are  1.52083 d
0.06 mo  are  1.82500 d
0.07 mo  are  2.12916 d
0.08 mo  are  2.43333 d
0.09 mo  are  2.73750 d
0.10 mo  are  3.04166 d
0.20 mo  are  6.08333 d
0.30 mo  are  9.12500 d
0.40 mo  are  12.16666 d
0.50 mo  are  15.20833 d
0.60 mo  are  18.25000 d
0.70 mo  are  21.29166 d
0.80 mo  are  24.33333 d
0.90 mo  are  27.37500 d
1 mo  corresponds to  30.41666 d
2 mo  are  60.83333 d
3 mo  are  91.25000 d
4 mo  are  121.66666 d
5 mo  are  152.08333 d
6 mo  are  182.50000 d
7 mo  are  212.91666 d
8 mo  are  243.33333 d
9 mo  are  273.75000 d
10 mo  are  304.16666 d
20 mo  are  608.33333 d
30 mo  are  912.50000 d
40 mo  are  1 216.66666 d
50 mo  are  1 520.83333 d
60 mo  are  1 824.99999 d
70 mo  are  2 129.16666 d
80 mo  are  2 433.33333 d
90 mo  are  2 737.49999 d
100 mo  are  3 041.66666 d
200 mo  are  6 083.33333 d
300 mo  are  9 124.99999 d
400 mo  are  12 166.66666 d
500 mo  are  15 208.33332 d
600 mo  are  18 249.99999 d
700 mo  are  21 291.66665 d
800 mo  are  24 333.33332 d
900 mo  are  27 374.99998 d
1 000 mo  are  30 416.66665 d

## Overview table : How many Day are in Month ?

Day d ⇒ Month mo
0.01 d  are  0.00032 mo
0.02 d  are  0.00065 mo
0.03 d  are  0.00098 mo
0.04 d  are  0.00131 mo
0.05 d  are  0.00164 mo
0.06 d  are  0.00197 mo
0.07 d  are  0.00230 mo
0.08 d  are  0.00263 mo
0.09 d  are  0.00295 mo
0.10 d  are  0.00328 mo
0.20 d  are  0.00657 mo
0.30 d  are  0.00986 mo
0.40 d  are  0.01315 mo
0.50 d  are  0.01643 mo
0.60 d  are  0.01972 mo
0.70 d  are  0.02301 mo
0.80 d  are  0.02630 mo
0.90 d  are  0.02958 mo
1 d  corresponds to  0.03287 mo
2 d  are  0.06575 mo
3 d  are  0.09863 mo
4 d  are  0.13150 mo
5 d  are  0.16438 mo
6 d  are  0.19726 mo
7 d  are  0.23013 mo
8 d  are  0.26301 mo
9 d  are  0.29589 mo
10 d  are  0.32876 mo
20 d  are  0.65753 mo
30 d  are  0.98630 mo
40 d  are  1.31506 mo
50 d  are  1.64383 mo
60 d  are  1.97260 mo
70 d  are  2.30137 mo
80 d  are  2.63013 mo
90 d  are  2.95890 mo
100 d  are  3.28767 mo
200 d  are  6.57534 mo
300 d  are  9.86301 mo
400 d  are  13.15068 mo
500 d  are  16.43835 mo
600 d  are  19.72602 mo
700 d  are  23.01369 mo
800 d  are  26.30137 mo
900 d  are  29.58904 mo
1 000 d  are  32.87671 mo

## Source information

As source for the information in the "Time units" category, we have used in particular:

## Last update on May 2, 2022

The pages of the "Time units" category were last editorially reviewed by Stefan Banse on May 2, 2022. They all correspond to the current status.

### Previous changes on April 24, 2021

• April 24, 2021: Publication of the time units converter.
• Editorial revision of all texts in this category