Months Between Dates Calculator
Count the full months and leftover days between two dates, with years, months and total days, including month-end dates like 31 January.
Your results
Calculation breakdown
- Months
- Count of complete calendar months between the two dates
- Remainder
- Leftover days after the last full month
- Month-end dates
- A month from the 29th–31st ends on the last day of a shorter month
Worked example
From 15/01/2026 to 02/04/2026 is 2 full months (to 15/03/2026) plus 18 remaining days. From 31/01/2026 to 01/03/2026 is 1 full month (to 28/02/2026) plus 1 day.
Assumptions
- Accounts for months of different lengths, including February in leap years.
- When the start date is the 29th, 30th or 31st, a full month ends on the last day of any shorter month.
- The order of the dates does not matter; the result is the gap between them.
How this calculator works
This calculator works out how many complete calendar months, plus any leftover days, sit between a start and end date. It's useful for tenancy agreements, loan terms, warranty periods or working out a baby's age in months.
Count full months and leftover days
The calculator counts complete calendar months from the earlier date, then the days left over. From 15 January to 2 April is two full months, to 15 March, plus 18 days. The order of the dates does not matter.
A month that starts on the 29th, 30th or 31st ends on the last day of a shorter month, so 31 January to 28 February 2026 is one full month and 31 January to 1 March is one month and one day.
When month counts matter
Month counts are used for leases, loan and phone contracts, warranties, probation periods and a baby's age. Contracts and legislation can define months differently, so check the wording of the agreement for how part months are treated.
The result also shows the gap as years, months and days and as a total number of days, which helps when a form asks for one format but your documents use another.
Frequently asked questions
How are partial months handled?
The calculator counts full calendar months first, then shows any remaining days that don't make up a further whole month.
Can I calculate months between today and a past date?
Yes, set either date to today to measure how many months have elapsed since or until an event.
Does it handle different month lengths?
Yes. Months of different lengths and leap years are handled, and a month from the 29th, 30th or 31st ends on the last day of a shorter month, so 31 January to 28 February is one full month.
Content responsibility
Maintained by CalcAussie and last updated 15 October 2026. Checks applied: calculation method, worked examples, Australian terminology, material assumptions, official references where an external rule applies, and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.