Age Calculator
Calculate exact age in years, months and days, plus total days, next birthday and day of birth.
Date Difference Calculator
Find the exact time between two dates, including working weekdays, or add and subtract days, weeks, months, years and business days from any date.
Use the Date Difference Calculator
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How to use the Date Difference Calculator
- Choose Difference or Add / subtract.
- Enter the dates (and amount and unit when adding or subtracting).
- Tick “inclusive” if the end date should count as a day.
- Read the result and copy the figures you need.
About this tool
Weekday counts exclude Saturdays and Sundays but not public holidays, which differ by country. Adding months keeps the same day of the month where possible and uses the last day of shorter months, so 31 January plus one month is 28 or 29 February.
Free to use. Your inputs are processed in your browser and are not sent to our servers. Results are estimates for general information; see the disclaimer.
Two calculators in one
- Difference between dates: years, months and days, plus total days, weeks, weekdays, weekend days and hours.
- Add or subtract time: days, weeks, months, years or business days from any date.
Counting the days between two dates
By default, the count doesn't include the end date. From 1 January 2026 to 31 December 2026 is 364 days. Tick Count the end date as a day to include it, which gives 365 days, the usual way to count when both dates are part of the period, such as leave or a contract.
| Use | Include end date? |
|---|---|
| Leave, hotel stays you pay for by day, contract periods | Usually yes |
| Time until a deadline or event | Usually no |
| Age or time since a date | No |
Business days and weekdays
Weekdays and business days are Monday to Friday. Saturdays and Sundays are excluded, but public holidays aren't, so subtract any holidays yourself.
In 2026, counting both 1 January and 31 December, there are 261 weekdays. If your workplace has a six-day week, the weekday count will be lower than your actual working days.
Adding or subtracting time: examples
| Start | Add | Result |
|---|---|---|
| Friday 6 November 2026 | 30 days | Sunday 6 December 2026 |
| Friday 6 November 2026 | 10 business days | Friday 20 November 2026 |
| 31 January 2026 | 1 month | 28 February 2026 |
When you add months, the date moves to the end of the month if that day doesn't exist, as in the last example.
Everyday uses
- Notice periods: find your last working day when you resign.
- Payment terms: work out when an invoice on 30-day terms is due.
- Project planning: count the business days left before a deadline.
- Leave: count how many weekdays a holiday will use.
- Visas and documents: check how long remains before something expires. Always confirm the official rules, which can count days differently.
To find someone's exact age from their date of birth, use the Age Calculator. To plan daily sales against a monthly target, try the Sales Target Calculator.
Frequently asked questions
Does it exclude public holidays?
No. Weekdays are Monday to Friday only.
What does inclusive mean?
Inclusive counting adds one day so that both the start and end dates are counted.
What is a business day?
Here it means Monday to Friday.
How do I count the days between two dates?
Enter a start date and an end date. Tick the inclusive option if both dates should count as days, such as for leave or a contract.
Does the business day count include public holidays?
No. It skips Saturdays and Sundays only, so subtract any public holidays yourself.
What happens when I add a month to 31 January?
The result moves to the last day of February, because February has no 31st.
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