Calculate the exact number of days between any two dates with business day, weekend, and holiday breakdowns.
The Number of Days Calculator computes the exact count of calendar days between any two dates, along with business days (weekdays), weekends, complete weeks, and other useful breakdowns. It handles dates in the past, present, and future with equal precision.
Day counting is one of the most fundamental date calculations. Lease durations, project timelines, interest calculations, travel planning, and deadline tracking all depend on accurate day counts. This calculator goes beyond simple subtraction by separating business days from weekends and providing percentage breakdowns.
The tool also includes a "days from now" quick calculator, handles leap years automatically, and shows the day-of-year number for both dates. Whether you're counting down to a vacation, calculating interest accrual days, or determining a project timeline, this calculator provides every day-related metric you need. Check the example with realistic values before reporting. Use the steps shown to verify rounding and units. Cross-check this output using a known reference case.
Accurate day counting is essential for contracts, deadlines, interest calculations, and project management. This calculator separates business from calendar days and handles all edge cases. Keep these notes focused on your current workflow. Tie the context to real calculations your team runs. Use this clarification to avoid ambiguous interpretation. Align the note with how outputs are reviewed.
Calendar Days = End Date - Start Date (in days). Business Days = Calendar Days - Weekend Days. Weekend Days = 2 × (Complete Weeks) + extra Saturday/Sunday. Weeks = Calendar Days / 7.
Result: 364 calendar days (260 business, 104 weekend)
From Jan 1 to Dec 31, 2025: 364 calendar days, 52 weeks, 260 weekdays (business days), and 104 weekend days.
The difference between calendar and business days creates frequent confusion. A "30-day" project deadline could mean 30 calendar days (~22 business days) or 30 business days (~42 calendar days). Always confirm which type is meant. Legal deadlines typically use calendar days. Project timelines often use business days.
Financial institutions use various day-count conventions. The "Actual/365" method counts exact calendar days divided by 365. The "30/360" method assumes 30 days per month and 360 days per year. The "Actual/Actual" method uses exact days and exact year length. These conventions affect interest calculations, bond pricing, and loan amortization.
A year has 365 days (366 in leap years). A week has 7 days. A quarter has roughly 91 days. A common month ranges from 28-31 days. There are approximately 260 business days per year and 104 weekend days. These are the fundamental numbers behind all date arithmetic.
By default, the calculator counts from the start date to the end date (not including start). You can toggle inclusive counting to include both endpoints.
Business days exclude Saturdays and Sundays. Major holidays are NOT automatically excluded — add those manually for precision.
Yes. The calculator correctly accounts for Feb 29 in leap years (2024, 2028, etc.).
Yes — if the start date is after the end date, the calculator shows the absolute difference with a note. Use this as a practical reminder before finalizing the result.
Use the "Add Days" section: enter a start date and number of days to find the resulting date. Keep this note short and outcome-focused for reuse.
January 1 is day 1, December 31 is day 365 (or 366 in leap years). Useful for Julian date references.