How to use Date Difference Calculator
- Choose the start date.
- Choose the end date.
- Tick Include the end date in the total if the last day counts.
- Days, weeks, months and weekdays update as you change the dates.
Example: Date Difference Calculator
Count the days from 1 January 2026 to 22 September 2026.
Options
- Include the end date in the total
- Adds one day to the total, and adds a weekday too only when the end date falls Monday to Friday. Use it for deadlines and periods where the final day counts.
- Also count weekdays (Monday to Friday)
- Drops Saturdays and Sundays only. Public holidays, bank holidays and shutdown days are not removed.
- Start date and End date
- YYYY-MM-DD with a calendar picker. If the end date is earlier, the tool swaps the pair and says so.
Supported inputs and limits
Where your input is processed
This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.
Why the same two dates can give two answers
Inclusive and exclusive counting both appear in contracts and everyday use, and the choice changes the answer by one day. A payment due within 30 days usually excludes the day the notice was given. A hotel stay from 1 January to 2 January is one night, an exclusive count, while a festival over the same two dates covers two calendar days. Both figures are correct for their own convention, so a calculator that shows the setting is clearer than one that hides it.
Questions about Date Difference Calculator
Should I include the end date or not?
From 1 January to 2 January is 1 elapsed day but 2 calendar days. Hotel nights and rental periods usually use the elapsed count, while a deadline or an event that runs on the final day uses the inclusive count.
Does a daylight saving change affect the count?
No. The tool compares calendar dates, so the spring forward and autumn back days still count as one day each.
How is the weekday figure worked out?
Saturdays and Sundays are removed. From 1 January to 15 April 2026 that leaves 74 weekdays out of 104 days. Public holidays are not considered.
What happens in a leap year?
The extra 29 February counts like any other day, and the result lists how many leap days fall inside the range.