Date Calculator Guide: How to Calculate Days Between Dates and More

1. Calculate Days Between Two Dates

The most common use case is finding out how many days are between two dates. Simply select your start date and end date, and the calculator instantly shows you the exact number of days. You can also choose to include or exclude the end date in your calculation, giving you flexibility for different scenarios.

This feature is perfect for:

• Counting down to special events (weddings, vacations, birthdays)
• Calculating project timelines and deadlines
• Determining rental or lease periods
• Tracking time since important milestones

2. Add or Subtract Time Periods

Need to know what date it will be 90 days from now? Or what date was 6 months ago? Our calculator lets you add or subtract years, months, weeks, or days from any date. You can combine multiple time units—for example, add 2 years, 3 months, and 15 days all at once.

This is incredibly useful for:

• Calculating maturity dates for investments or certificates
• Planning future events or deadlines
• Determining expiration dates
• Finding historical dates by subtracting time periods

3. Business Days Calculation

When you need to calculate working days (excluding weekends), our business days feature comes in handy. Simply enable the "Business Days" option when adding or subtracting days, and the calculator automatically skips Saturdays and Sundays.

This feature is essential for:

• Project planning and deadline management
• Calculating delivery dates for business operations
• Determining processing times for applications
• Planning work schedules and timelines

4. Real-Time Results

Our date calculator provides instant results as you change your inputs. There's no need to click a calculate button—the results update automatically, making it fast and efficient to try different date combinations.

5. Privacy and Security

All calculations happen locally in your browser. We don't store, upload, or track any of your date inputs or results. Your privacy is completely protected, making it safe to use for sensitive date calculations.

Calculating Days Between Two Dates

1. Select your start date: Click on the start date field and choose your beginning date from the calendar picker or type it in the format YYYY-MM-DD.
2. Select your end date: Choose your end date using the same method.
3. Choose to include end date (optional): If you want to count the end date in your calculation, check the "Include end date" option. This is useful when calculating inclusive periods.
4. View your results: The calculator instantly displays the number of days between your selected dates.

Adding or Subtracting Time from a Date

1. Enter your base date: Select the date you want to start from.
2. Choose add or subtract: Select whether you want to add time (move forward) or subtract time (move backward).
3. Enter time periods: Input the number of years, months, weeks, and/or days you want to add or subtract. You can use any combination—for example, just days, or years and months together.
4. Enable business days (optional): If you only want to count working days, check the "Business Days" option to exclude weekends.
5. See your result: The calculator shows you the resulting date instantly.