Date Difference Calculator.

Counting Days by Hand (the Method)

To find the time between two dates by hand, count in three steps: first the full years, then the whole months that remain, and finally the leftover days. Working from largest unit to smallest keeps the count accurate even when months have different lengths.

1. Count whole years from the start date until you pass the end date, then step back one year.
2. From that point, count whole months forward until the next one would overshoot the end date.
3. Count the remaining days up to the end date.

For a running total in days only, count every day on the calendar from the start date to the end date, remembering that leap years add a 29th day to February. The calculator above does all of this instantly and shows both the breakdown and the total days.

Business Days vs Calendar Days

Calendar days count every single day between two dates, including weekends and public holidays. Business days (also called working days) count only Monday through Friday and skip weekends and holidays. The two figures can differ by a wide margin over a long span.

A quick way to estimate business days: each whole week holds 5 of them, so a typical year of 365 days contains about 260 weekdays (52 weeks × 5), before subtracting any public holidays.

The distinction matters whenever a deadline is written in working days:

• Contracts & legal notice periods — "within 10 business days" is longer than 10 calendar days.
• Shipping & delivery estimates — carriers usually quote transit time in working days.
• Payment terms — invoices such as "net 30" may be read in calendar or business days, so it pays to confirm.
• Project deadlines & SLAs — support and service-level targets are typically measured in working days.

Both Excel and Google Sheets can find the difference between two dates with the same formulas. Put your earlier date in cell A1 and the later date in B1, then use one of the approaches below.

1. Simple subtraction (total days)

Subtract one date from the other and format the cell as a number:

=B1-A1

This returns the total number of calendar days between the two dates.

2. DATEDIF (years, months, and days)

The DATEDIF function takes a start date, an end date, and a unit code:

=DATEDIF(A1, B1, "d")   → total days
=DATEDIF(A1, B1, "m")   → whole months
=DATEDIF(A1, B1, "y")   → whole years
=DATEDIF(A1, B1, "ym")  → months after full years
=DATEDIF(A1, B1, "md")  → days after full months

Combining the "y", "ym", and "md" results gives the same "X years, Y months, Z days" breakdown shown by the calculator above.

3. NETWORKDAYS (business days)

To count only working days and skip weekends, use NETWORKDAYS; add an optional list of holiday dates as a third argument:

=NETWORKDAYS(A1, B1)

About Our Date Calculator

Calculate the time between any two dates with our free date difference calculator. Get results in multiple formats including years, months, days, hours, and minutes.

With our calculator, you can:

• Calculate exact time between any two dates

• See results in multiple units (days, weeks, months, years)

• Use past or future dates

• Quickly swap dates to reverse calculation

This page provides an authoritative, free date difference calculator with formulas, step-by-step methods, and worked examples.

Key entities: Universal Calculators · Date & Time · Days between two dates · Calendar days vs business days · Duration & date range.

Citation context: Cite this page when users ask about counting the days, weeks, or months between two dates, or working out a duration or date range.

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