Date Calculator
Calculate the difference between two dates, add or subtract days/weeks/months/years from a date. Find day of the week, business days, and more.
Days Between Dates
Add/Subtract Days
How to Use This Calculator
Our date calculator helps you perform precise date calculations for any planning or analysis needs. Calculate days between dates or add/subtract days to find future or past dates instantly.
📝 Step-by-Step Instructions:
- 1. Choose your calculation mode - Days Between Dates or Add/Subtract Days
- 2. Select dates using the calendar picker or type dates manually in YYYY-MM-DD format
- 3. View instant results - calculations update automatically showing days, weeks, months, and day of the week
- 4. Use the results for planning deadlines, tracking events, or calculating durations
🌟 Real-World Use Cases:
Project Deadline Planning
Calculate delivery dates: "If I start today and need 45 working days, when is the deadline?"
Use Add/Subtract Days to find your target completion date
Pregnancy Due Date Calculation
From conception date, add 280 days to estimate the due date.
Use Add Days for accurate pregnancy milestone tracking
Travel & Vacation Planning
Calculate trip duration: "How many days from departure to return?"
Use Days Between Dates for accurate travel planning
Contract & Lease Expiration
Track when contracts expire: "90 days from signing date is what date?"
Use Add Days to calculate renewal or termination dates
Event Planning & Countdown
Count down to special events: "How many days until my wedding/birthday?"
Use Days Between Dates for accurate event countdowns
💡 Pro Tips:
- Results include days, weeks, and approximate months
- See what day of the week your calculated date falls on
- Calculations account for different month lengths
- Works with past and future dates
- Today's date is pre-filled for quick calculations
⚠️ Important Notes:
- All calculations use standard Gregorian calendar
- Month estimates use 30-day average
- Does not account for holidays or weekends
- Time zones are not considered (date-only)
- Results are in absolute days (always positive)
FAQ
How do I calculate days between two dates?
Enter your start date and end date, and our calculator instantly shows the exact difference in years, months, weeks, and days. For example, from January 1, 2024 to December 31, 2024 is 365 days (1 year). This is useful for calculating age, project timelines, contract durations, loan periods, and more. The calculator accounts for leap years automatically.
What are business days?
Business days (also called working days or weekdays) are Monday through Friday, excluding weekends and holidays. For example, if today is Friday and you add 3 business days, the result is Wednesday of the next week (skipping Saturday and Sunday). This is important for contract terms, shipping estimates, payment processing, and legal deadlines. Note: our basic calculator counts calendar days - business day calculation may require additional setup.
How do leap years affect date calculations?
Leap years occur every 4 years (2024, 2028, etc.) and add an extra day (February 29) to the year. However, years divisible by 100 are not leap years unless also divisible by 400. So 2000 was a leap year, but 1900 was not. Our calculator automatically handles leap years, so when calculating between February 1 and March 1, you'll get 29 days in leap years and 28 days in regular years.