Date Calculator

Frequently Asked Questions

How do I calculate days between two dates?

To calculate days between dates, subtract the earlier date from the later date. Account for varying month lengths (28-31 days) and leap years. For example, from January 15 to March 22 in a non-leap year: 16 remaining days in Jan + 28 days in Feb + 22 days in Mar = 66 days. Our calculator handles all date math automatically, including leap years.

How many weeks are between two dates?

To find weeks between dates, first calculate the total days, then divide by 7. For 66 days: 66 ÷ 7 = 9 weeks and 3 days. Our calculator shows results in years, months, weeks, and days for complete clarity. This is useful for project planning, pregnancy tracking, or scheduling.

How do I add or subtract days from a date?

To add days to a date, count forward from that date. To subtract, count backward. Remember month boundaries and leap years. Adding 90 days to January 1, 2026 gives April 1, 2026 (31 + 28 + 31 = 90). Date calculators handle month-end rollovers and leap years automatically.

What are business days and how do I calculate them?

Business days (also called working days or weekdays) exclude weekends (Saturday and Sunday) and typically holidays. In a standard month, there are approximately 20-23 business days. To calculate: count total days, then subtract weekends (roughly 2 per 7 days). For 30 calendar days, expect about 22 business days, minus any holidays.

What date is X days from now?

To find a future date, add the number of days to today's date. For 90 days from today, the calculator accounts for varying month lengths. Use this for deadline tracking, warranty expiration dates, or countdown planning. Our calculator instantly computes dates for any number of days, forward or backward.

How do leap years affect date calculations?

Leap years occur every 4 years (2024, 2028, etc.) when February has 29 days instead of 28. This affects day counts between dates that span February. The rule: a year is a leap year if divisible by 4, except century years must be divisible by 400. So 2000 was a leap year, but 1900 was not.

How do I calculate my age in days, weeks, or months?

Enter your birth date as the start date and today as the end date. The calculator shows total days, weeks, months, and years. For example, someone born January 1, 1990 is approximately 12,800 days old (35+ years × 365.25 days). Our age calculator provides even more detailed breakdowns.

What is the difference between calendar days and business days?

Calendar days include every day on the calendar (weekdays and weekends). Business days only count Monday through Friday, excluding weekends and often public holidays. A 14-calendar-day period contains 10 business days. Legal deadlines often specify which type applies.

How do I calculate payroll periods and pay dates?

For biweekly payroll (every 2 weeks), add 14 days to each pay date. For semi-monthly (1st and 15th), use fixed dates. Monthly periods end on the last day of each month. Our calculator helps determine pay period end dates and when checks will be issued.

How do I track warranty or contract expiration dates?

Enter the purchase or start date, then add the warranty period (e.g., 365 days for 1 year, 730 for 2 years). The calculator shows the exact expiration date. For example, a 90-day return policy starting January 15 expires April 15. Track multiple warranties by calculating each separately.

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