Date to Date Calculator

Days between two dates

The date difference calculator counts the total number of calendar days between a start date and end date, inclusive of neither endpoint by default — the same convention used by most date calculation tools and spreadsheet software. It also breaks down the difference into years, months, and remaining days.

Working days vs. calendar days

Working days (also called business days) count only Monday through Friday, excluding weekends. This is essential for project planning, legal deadlines, and contract timelines. The calculator does not account for public holidays — add or subtract holidays manually for precise business day counts.

Add or subtract days from a date

The "Add / Subtract Days" mode lets you find the date that is exactly N days from any starting date. Enter a positive number to move forward in time, or a negative number to go back. This is useful for calculating deadlines, warranty expiry dates, payment due dates, and planning future events.

Common date calculations

• Days until a holiday or event
• Days since a past event (anniversary, start of a project)
• 90-day notice periods
• Contract deadlines and payment terms
• How many weekdays remain in the month or quarter