Date Calculator
Find the number of days between two dates, or add and subtract days from any date. Instant results.
Quick Reference — Common Date Ranges
| Period | Days | Weeks |
|---|---|---|
| 1 Month (avg) | 30 | 4 weeks, 2 days |
| 3 Months (avg) | 91 | 13 weeks |
| 6 Months (avg) | 182 | 26 weeks |
| 1 Year | 365 | 52 weeks, 1 day |
| 1 Leap Year | 366 | 52 weeks, 2 days |
| 2 Years | 730 | 104 weeks, 2 days |
How to Calculate Days Between Dates
To find the number of days between two dates, subtract the earlier date from the later date. This calculator handles all the complexity of varying month lengths, leap years, and crossing year boundaries. Simply enter your start and end dates and get an instant result showing total days, weeks and remaining days, and months and remaining days.
For example, the number of days from January 1 to July 1 in a non-leap year is 181 days (25 weeks and 6 days). In a leap year, it is 182 days because February has 29 days instead of 28.
Business Days vs Calendar Days
Calendar days count every day including weekends and holidays. Business days (or working days) typically exclude Saturdays, Sundays, and public holidays. This calculator counts calendar days. As a rough guide, multiply calendar days by 5/7 to estimate business days, though this does not account for holidays.
For example, 30 calendar days is approximately 21–22 business days. A 90-day deadline is roughly 64 business days.
Common Use Cases
Deadlines: Calculate how many days until a project is due, or find the exact date N days from now.
Countdowns: Find out how many days until a holiday, birthday, wedding, or other event.
Age and duration: Calculate the exact number of days between two life events.
Legal and financial: Many contracts, leases, and financial instruments reference specific day counts (30-day notice, 90-day warranty, 365-day return policy).
Frequently Asked Questions
- How many days are between two dates?
- Enter both dates into this calculator to find the exact number of calendar days. For example, from January 1 to March 1 in a non-leap year is 59 days.
- How do I calculate 30 days from today?
- Use the Add / Subtract Days tab. Select today's date, enter 30, and choose Add. The result shows the exact date 30 days from now and what day of the week it falls on.
- How many days until Christmas?
- Enter today's date as the start date and December 25 of the current (or next) year as the end date. The calculator will show the exact number of days remaining.
- How many weeks are in a year?
- A standard year has 52 weeks and 1 day (365 days). A leap year has 52 weeks and 2 days (366 days).
- How do I add days to a date?
- Use the Add / Subtract Days tab. Pick a starting date, enter the number of days, select Add, and get the resulting date instantly.