Months to Days Converter
Convert months to days — using the average month of 30.44 days, since real months vary. Results update as you type; exact factors shown.
One month (average, 30.4369 days) is 30.4369 days — see the exact factor, not a rounded rule of thumb.
How the months to days converter works
Time converts through the second. Minutes, hours, days and weeks are exact multiples. A month is taken as the Gregorian average (30.436875 days) and a year as the Gregorian average (365.2425 days = 31,556,952 s); calendar months and leap years vary from these averages.
The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.
Common time conversions
| From | To | Units |
|---|---|---|
| 1 mo | 30.4369 d | month (average, 30.4369 days) to days |
| 2 mo | 60.8738 d | month (average, 30.4369 days) to days |
| 3 mo | 91.3106 d | month (average, 30.4369 days) to days |
| 6 mo | 182.6213 d | month (average, 30.4369 days) to days |
| 9 mo | 273.9319 d | month (average, 30.4369 days) to days |
| 12 mo | 365.2425 d | month (average, 30.4369 days) to days |
| 18 mo | 547.8638 d | month (average, 30.4369 days) to days |
| 24 mo | 730.485 d | month (average, 30.4369 days) to days |
| 36 mo | 1,095.7275 d | month (average, 30.4369 days) to days |
| 48 mo | 1,460.97 d | month (average, 30.4369 days) to days |
| 60 mo | 1,826.2125 d | month (average, 30.4369 days) to days |
| 120 mo | 3,652.425 d | month (average, 30.4369 days) to days |
Units in this converter and their exact factors
| Unit | Symbol | One unit in seconds |
|---|---|---|
| millisecond | ms | 0.001 second |
| second | s | 1 second |
| minute | min | 60 second |
| hour | h | 3,600 second |
| day | d | 86,400 second |
| week | wk | 604,800 second |
| month (average, 30.4369 days) | mo | 2,629,746 second |
| year (365.2425 days) | yr | 31,556,952 second |
FAQFrequently asked questions about time conversion
How many days in a month?
Between 28 and 31. This uses the average of 30.44 days, a twelfth of the average year.
Why not just use 30?
Because that loses five days a year, which matters over any long period.
How many days is 3 months?
About 91 on average, though a specific three months can be 89 to 92.
When does the average mislead?
For anything contractual — count the actual dates with the days-between calculator instead.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Physical Laboratory (NPL) — United Kingdom's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.