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Date difference calculator

Count the days, weeks and months between two dates.

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Open Date difference calculator and you get an answer straight away, with no account to create. You will find it under Dates & time, with Add or subtract days from a date and Days until date calculator for the neighbouring cases.

How to use it

  1. Open the tool — no signup or install needed.
  2. Enter your input or adjust the available options.
  3. Get your result instantly, then copy or download it.

Frequently asked questions

What does Date difference calculator do?

Count the days, weeks and months between two dates.

When would I actually use this?

Answering a scheduling question exactly: how many working days until a deadline, what date falls sixty days out, and what time that is for a colleague elsewhere.

What is the most common mistake?

Counting days by subtracting dates and forgetting whether the endpoints are included. Inclusive and exclusive counts differ by one, which is the difference between meeting a deadline and missing it.

How is Date difference calculator different from Add or subtract days from a date?

They sit next to each other but answer different questions: Add or subtract days from a date is the one to open when you need it to find the date a number of days before or after a starting date. Pick whichever matches what you're starting from — both are free.

Is there a tool for the next step?

Days until date calculator is the closest one after this: Count the number of days from today until a future date.

What else is worth having open alongside it?

Date Calculator and Date Pattern Generator — they come up in the same task often enough to be worth a second tab.

Where do the figures come from?

Calendar arithmetic follows the proleptic Gregorian calendar and the IANA time-zone database, so daylight-saving transitions and leap years are handled. Public holidays vary by country and region and are not assumed.

Further reading

All guides →
How-toHow Many Days Between Two DatesSubtract the earlier date from the later, minding month lengths and leap years. Here's how to count it, and whether to include both endpoints.ExplainerWorking Remotely From Another Country: Where the Tax Is Actually DueThe 183-day rule is the most repeated and least understood sentence in cross-border work. It comes from one article of one model treaty, it has three conditions and not one, and it decides nothing at all about social security, payroll or your employer's exposure. Here is what each rule actually tests.How-toHow to Add or Subtract Days from a DateCount forward to add, backward to subtract, rolling over month ends. Here's how, why month lengths and leap years trip you up, and when weekends count.How-toHow Many Days Until a Date? (With Worked Examples)Count the days until any future date, understand inclusive vs. exclusive counting, and build an accurate countdown you can trust.ExplainerHow Many Working Days Are There in a Year?A year has roughly 260 weekdays before holidays. Learn where that number comes from, why it varies by country, and how public holidays bring it down to the working days you actually get.How-toHow to Add and Subtract Time (Hours and Minutes)Add and subtract hours and minutes reliably. Learn to carry over 60, borrow when subtracting, and handle a result that crosses midnight into the next day.