All of the 12 months of the year have at least 28 days and a maximum of 31 days.
Some months have 30 days how many have 28
The calendar used in the modern world is created based on the Gregorian calendar named after Pope Gregory XIII.
As per the Gregorian calendar, a year is divided in 12 months such that every month has at least 28 days and a maximum of 31 days.
In this calendar, the month of February has the lowest number of days that is 28 in a normal year while 29 in a leap year. Other than February, all months have more than 28 days.
The months of April, June, September, and November have 30 days while the months of January, March, May, July, August, October, and December have 31 days.
What is a leap year and why February has 29 days in a leap year?
The number of days in the calendar is determined by the time taken by Earth to revolve around the sun. Typically, Earth takes about 365.25 days to complete a revolution around the Sun. However, a normal year in a calendar is consists of only 365 days. To accommodate the extra time (0.25 days) taken by the Earth, the calendar has introduced a Leap year with 366 days which comes every 4 years. This leap year helps to round off a normal year to 365 days. The leap year comes every 4 years because the extra 0.25 days taken by the Earth becomes a complete 1 day (24 hours) at the end of the 4 years.
| Year | # of days in a year (as per earth revolution) | # of days in a year (as per calendar) |
|---|---|---|
| 1 | 365.25 | 365 |
| 2 | 365.25 | 365 |
| 3 | 365.25 | 365 |
| 4 | 365.25 | 366 (Leap Year) |
| Total # of days | 1461 | 1461 |
Modern calendar based on the Gregorian calendar
| S.No. | Month | # of Days (Normal year) | # of Days (Leap Year) |
|---|---|---|---|
| 1 | January | 31 | 31 |
| 2 | February | 28 | 29 |
| 3 | March | 31 | 31 |
| 4 | April | 30 | 30 |
| 5 | May | 31 | 31 |
| 6 | June | 30 | 30 |
| 7 | July | 31 | 31 |
| 8 | August | 31 | 31 |
| 9 | September | 30 | 30 |
| 10 | October | 31 | 31 |
| 11 | November | 30 | 30 |
| 12 | December | 31 | 31 |
| Total number in year | 12 months | 365 | 366 |
Now you must be wondering,
Why this extra day in a leap year is adjusted in the month of February?
The extra day is added to the February month because it is necessary to match with the movement of Earth around the Sun.
You must be curious,
Why don’t all months in a year have the same number of days?
The number of days in a month are determined based on the lunar cycle. The lunar cycle is the cycle in which the moon changes its phase from full moon to new moon and vice versa over the period of a synodic month (about 29.53 days). We can’t divide 365 days by 29.53 days to get an integer number. Therefore, ancient Romans came up with months having 30 and 31 days to accommodate 365 days. Thus, all months in a year don’t have the same number of days.
Read: 🌚Do We Always See The Same Side Of The Moon?
Question: How many months have 30 days?
Answer: There are 4 months – April, June, September and November that have 30 days .
Question: How many months have 31 days?
Answer: There are 7 months – January, March, May, July, August, October, and December that have 31 Days.
So if you are wondering about the “how many months have 28 days” riddle. The answer to the riddle is 12 months because all 12 months have 28 or more days.
