Date Duration Calculator
Count the days between two dates – with the option to include the end day, and a separate count of working days only. You also get the duration expressed in years, months and days, plus totals in weeks, hours and minutes.
Useful for project deadlines, notice periods, holiday planning, contract terms, pregnancy weeks, subscription lengths and anywhere a precise day count matters.
How to use the date duration calculator
Pick your start date.
Pick your end date.
Choose whether the end day counts, and read the results.
Why use the Convert Now date duration calculator
Working days
Weekday-only counts for business deadlines.
Both conventions
Include or exclude the end date with one setting.
Full breakdown
Years, months, days, weeks, hours and minutes.
Leap-year accurate
Uses the real calendar throughout.
Why "days between" is ambiguous
Ask how many days there are from Monday to Friday and you will get two answers: four (the gaps between them) or five (the days themselves). Contracts, notice periods and hotel bookings differ in which they mean, and getting it wrong by one day can matter. The "count the end day" option lets you switch between the two conventions explicitly, so you can match whatever your document specifies.
Working days
The weekday count excludes Saturdays and Sundays, which is the usual basis for business day calculations in delivery times, payment terms and legal deadlines. It does not know about public holidays, which vary by country and even by region, so for a legally exact deadline subtract the relevant holidays yourself.
Months are not a fixed length
The years-months-days breakdown walks the calendar properly rather than assuming a 30-day month, so "1 month" from 31 January behaves the way a person would expect. The approximate month total in the statistics uses the average month length of 30.44 days, which is the right tool for rough comparisons but not for legal dates.
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Frequently asked questions
How do I calculate the number of days between two dates?
Enter a start and end date. The total appears immediately, along with weeks, months and a working-day count.
Should I include the end date?
It depends on the document. Notice periods and rental terms often count both endpoints; simple duration questions usually do not. Use the dropdown to switch.
How many working days are between two dates?
The result shows weekdays only, excluding Saturdays and Sundays. Public holidays are not deducted.
Does it handle leap years?
Yes. All counts use the real calendar, so 29 February is included whenever it falls in the range.
Can I calculate a date in the past?
Yes – if the end date is earlier than the start date, the duration is still calculated and the result notes the reversal.
Is it free?
Yes, with no limits or sign-up.
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