Date Calculator Free · Calc Pro
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Coming soonHow many days until a deadline, a trip or a birthday? Enter two dates and Calc Pro counts the days between them, plus the 30/360 day count that banks and bond markets use for interest.
How to use the Date Calculator
- 1Tap Start Year and enter the year, then press ↓ to enter the Start Month (1 to 12) and Start Day.
- 2Enter the End Year, End Month and End Day the same way.
- 3Tap Difference and press Calc to see the number of days, and the Difference 360 count.
Actual days vs 30/360
| Method | How it counts | Used for |
|---|---|---|
| Difference | Actual calendar days | Deadlines, events, countdowns |
| Difference 360 | Every month is 30 days | Interest on many bonds, loans and mortgages |
For January 1 to December 25, 2026, the actual count is 358 days, while 30/360 gives 354, because months like January and March count as 30 days instead of 31.
Frequently Asked Questions
Does the count include the start and end dates?
Difference is the number of days from the start date to the end date, so January 1 to January 2 is 1 day. Add 1 if you want to count both dates.
What is Difference 360?
It's the 30/360 day count, which treats every month as 30 days and a year as 360. Banks and bond markets use it to calculate interest on many loans and bonds.
Does it handle leap years?
Yes. The Difference counts actual calendar days, including February 29 in leap years.
Can I work with times as well as dates?
Yes. Calc Pro's Date and Time calculator measures the time between two dates in days, hours, minutes and seconds, and adds or subtracts days and times from a date. Open it from the side menu.
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Take the Date Calculator with you
The Date Calculator is free in Calc Pro for iPhone and iPad, along with 10 calculators in one app.
Coming soonFree with ads · In-app purchase unlocks the full Pro Premium version
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