Date Difference Calculator - Days Between Two Dates
Count the days, working days, weeks, months and years between two dates — or add and subtract any period from a date and get the exact result.
Used for the working-day count.
❌ Enter two valid dates.
Dates are handled in UTC so results never shift with your time zone. Month arithmetic clamps to the last valid day, so 31 January plus one month gives 28 (or 29) February.
What is a Date Difference Calculator?
A date difference calculator measures the span between two dates and expresses it in every unit you might need — total days, calendar years and months, weeks, hours, and working days with weekends excluded. It also works in the other direction, adding or subtracting years, months, weeks and days from a starting date to land on an exact result date.
Working Days and the Gulf Weekend
Most online date calculators assume a Saturday–Sunday weekend, which quietly produces wrong answers in Saudi Arabia, the UAE and much of the Gulf, where the weekend falls on Friday and Saturday. This calculator lets you choose, so the working-day count matches your actual calendar. Public holidays vary by country and year and are not deducted — subtract your local holidays from the working-day figure yourself.
- Total days between any two dates
- Calendar difference in years, months and days
- Working days with a selectable weekend (Fri–Sat, Sat–Sun, Fri only, or none)
- Weeks, hours and minutes
- Optional "include the end day" for leave and stay counting
- Add or subtract years, months, weeks and days from any date
- The weekday of every date shown
Common Use Cases
Project Deadlines
Count the working days available before a delivery date.
Leave Planning
Work out how many leave days a date range consumes.
Notice Periods
Find the exact last working day of a notice period.
Visa Validity
Check how long a permit or residency remains valid.
Invoice Due Dates
Add 30, 60 or 90 days to an invoice date instantly.
Contract Terms
Find the end date of a 2-year or 18-month agreement.
How to Use the Calculator
- Choose a mode: days between two dates, or add and subtract from a date.
- Enter your dates.
- Pick the weekend convention that applies where you are.
- Tick "include the end day" when counting a duration you occupy, such as leave days or hotel nights.
- Read the totals, working-day count and weekday details.
Should You Include the End Day?
This single checkbox is the source of most off-by-one disputes. Use it when you are counting days you occupy: annual leave from Monday to Friday is five days, not four. Leave it off when you are measuring the gap between two points: from Monday to Friday is four days of elapsed time. Payroll, hotels and courts each have their own convention, so check which one applies before you file anything.
How Month Arithmetic Handles Overflow
Adding one month to 31 January is ambiguous, because February has no 31st. This calculator clamps to the last valid day, giving 28 February (or 29 in a leap year) rather than overflowing into March. That is the convention used by most contract and finance systems. Years are added the same way, so 29 February plus one year lands on 28 February.
Why Calendar Difference and Total Days Differ
"3 months and 5 days" and "96 days" can describe the same span. The first is a calendar description that depends on which months are involved; the second is an exact tally. Neither is wrong — use the calendar form for contracts and ages, and the day count for interest, penalties and anything billed per day.
Who This Calculator Is For
- Project managers counting available working days
- HR and payroll teams calculating leave and notice
- Finance teams setting invoice and payment dates
- Legal and contract administrators tracking terms
- Anyone managing a visa, permit or renewal deadline
- Students and researchers measuring date ranges
❓ Frequently Asked Questions
How do I count the days between two dates?
Enter a start and end date and the calculator returns the total number of days, plus the difference expressed as years, months and days.
Should I include the end day?
Include it when you are counting a duration you occupy — leave days, hotel nights billed inclusively, or event days. Leave it off when measuring the gap between two moments.
How are working days calculated?
The calculator walks through every day in the range and excludes the weekend days you select. Saudi Arabia and the UAE use Friday and Saturday, while most other countries use Saturday and Sunday.
Does it exclude public holidays?
No. Public holidays vary by country, region and year, so only weekends are excluded. Subtract your local holidays from the working-day figure manually.
How does adding months work?
Months are added calendar-wise and the day is clamped to the last valid day of the target month, so 31 January plus one month gives 28 (or 29) February rather than overflowing into March.
Can I subtract time from a date?
Yes. Switch to the add/subtract mode and choose 'Subtract' to move backwards by any combination of years, months, weeks and days.
Why do years, months and days not match the total day count exactly?
Because calendar months have different lengths. '3 months and 5 days' is a calendar description, while the total day count is an exact tally.
Does my time zone change the result?
No. All dates are handled in UTC so results are identical wherever you are.
What can I use this for?
Project deadlines, notice periods, contract durations, visa validity, leave planning, pregnancy dates, invoice due dates and age gaps.
Is this tool free?
Yes. It is completely free, needs no sign-up, and runs entirely in your browser.