Date Difference Calculator
Calculate the number of days, weeks, months, and years between two dates, or add days to a date.
Processed on your device. Nothing you type is sent anywhere.
How to use: Date Difference Calculator
- Choose the start date and end date.
- Select whether to include the last day in the count.
- See the total in days, weeks, months, hours, and minutes.
- Use the section below to add or subtract days, months, and years from a date.
About this tool
The difference is calculated using the actual calendar, accounting for leap years and months with 28 to 31 days. For months, we use calendar months: January 31 to February 28 counts as one full month, since February doesn't have a 31st day.
By default, the count excludes the first day and includes the last (as in “10 days from now”). To count both dates—the way you might for hotel stays or leave periods—select “include the last day.” For deadlines counted in business days only, use the business day calculator.
Frequently asked questions
How do I find out how many days are left until a date?
Leave the start date as today (it’s prefilled) and choose your target date as the end date. The result shows the calendar days and the equivalent in weeks and months.
Does the calculator account for leap years?
Yes. All calculations use the actual Gregorian calendar, including February 29 in leap years.
What's the difference between calendar days and business days?
Calendar days include every day of the week. Business days exclude weekends and holidays. For business days, use the business day calculator.
Is it really free? Is there a daily limit?
It's free with no daily limits. Processing happens on your device, so there's no per-use cost and no need to limit you.
Does it work on phones?
Yes. The site works in any modern browser on Android, iPhone, Windows, Mac, and Linux—no installation needed.
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