Date Difference Calculator
Enter two dates to see the difference as years, months and days, plus the totals in months, weeks and days.
Last updated November 2, 2026
Defaults to today
Result
3 years, 7 months, 28 days
43 months · 191 weeks · 1,338 days in total
Show the work
- The earlier date, March 15, 2023, is day zero. The later date is November 12, 2026.
- Whole years between the dates: 3 years.
- Whole months after those years: 7 months.
- Remaining days after the months: 28 days.
- Totals: 43 months, 191 weeks and 1 day, or 1,338 days in all.
How the difference between dates is calculated
difference = later date − earlier date, in whole years, then whole months, then the remaining days
The calculator takes the earlier date as the start, counts complete calendar years, then complete months, and finally the days left over. The order of the two dates does not matter: the result is always the size of the gap.
Totals are shown separately: total months are the complete months in the gap, total weeks are the complete 7-day blocks, and total days are the days elapsed after the earlier date. Dates are calendar dates, so time zones do not change the answer.
Adding months follows one rule: if the target month is shorter, the date lands on its last valid day. January 31 plus one month is February 28 (February 29 in a leap year). That rule is what keeps the month count stable at month ends.
See how we calculate for the formulas, sources and review schedule behind every calculator.
Also useful alongside this calculator: Business Days Calculator and Date To Date Calculator.
Month ends and leap years
From January 31 to March 1, 2026 is 29 days, and the calculator shows 1 month and 1 day. Adding one month to January 31 gives February 28, the last valid day, and the extra day after it reaches March 1. January 31 to February 28 on its own is 0 months and 28 days, because the month is only counted once the end date passes February 28. In 2024, a leap year, the gap is 30 days but the answer is still 1 month and 1 day, because February 29 exists.
Months are not a fixed number of days, so a months-and-days answer and a total-days answer can look unrelated. January 15 to February 14, 2026 is 30 days and not yet a full month. January 15 to February 15 is 31 days and exactly 1 month.
One year is not always the same number of days
January 1, 2026 to January 1, 2027 is 1 year, 0 months and 0 days, which is 365 days. January 1, 2024 to January 1, 2025 is also exactly 1 year, but it is 366 days because February 29, 2024 falls inside it. Use the total days when exact elapsed time matters, for example for a billing period, and the years, months and days form when you want a description a person can read.
Counting both the first and last date
The earlier date is day zero, so March 10 to March 14 is 4 days. That matches nights in a hotel stay, but it lists 5 calendar dates. If you need both ends included, add 1 to the total days. The years, months and days figures are not affected by this choice.
How to use the Date Difference Calculator
- Enter the first date.
- Enter the second date. The order does not matter.
- Read the difference in years, months and days, with totals for months, weeks and days.
- Open "Show the work", or use Copy, Print or Share.
Worked example
The difference between Wednesday, March 15, 2023 and Monday, October 19, 2026 is 3 years, 7 months and 4 days. The same gap is 43 complete months, 187 complete weeks, or 1,314 days. To follow the steps by hand: three whole years from March 15, 2023 end on March 15, 2026. Seven more months reach October 15, 2026, and four more days reach October 19. The 1,314 days include one leap day, February 29, 2024. Entering the dates in the opposite order gives the same result.
| Year | Days | Leap year |
|---|---|---|
| 2022 | 365 | No |
| 2023 | 365 | No |
| 2024 | 366 | Yes |
| 2025 | 365 | No |
| 2026 | 365 | No |
| 2027 | 365 | No |
Frequently asked questions
Does the order of the dates matter?
No. The result is the size of the gap, so entering the later date first gives the same numbers.
Are the first and last dates both counted?
No. The earlier date is day zero, so the total days are the days elapsed after it. Add 1 if you want to count both ends.
How are months of different lengths handled?
Months are counted as complete calendar months. If the later date falls on an earlier day of the month than the first date, the last month is not complete yet, so those days are counted as remaining days.
Why do two gaps with the same number of months have different totals in days?
Calendar months have 28, 29, 30 or 31 days. Three months from January 15 is 90 days in a common year, and three months from July 15 is 92 days.
Are my dates stored or sent anywhere?
No. The calculation runs in your browser and nothing you enter is saved or uploaded.