Months between dates calculator
Find how many months lie between two dates, such as a service period, a lease or a baby's age in months.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter start date and end date.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Whole months = the largest n where (start + n months) does not pass the end, using the last day of a shorter month. Extra days = end − (start + n months).
Example
Inputs: Start date = 2024-01-15, End date = 2026-10-01. Result: Whole months: 32; Extra days: 16; In years, months and days: 2 years, 8 months, 16 days.
Limits and caveats
- Month counting rules differ between contracts; some treat 31 January to 28 February as a month and some do not. This tool counts it as a whole month.
Questions about this tool
When is a month complete?
When the end reaches the same day number in a later month, or that month's last day if it is shorter.
Why not divide the days by 30?
Months run from 28 to 31 days, and calendar counting gives the figure that matches contract dates.
How do I get my baby's age in months?
Enter the birth date as the start and today as the end to see whole months and extra days.