General tool

Date Difference Calculator

Find days, weeks, months, business days, and calendar duration between two dates.

Calculator

Enter values

Results update automatically as soon as enough values are available.

General

Result

About this calculator

How it works

A date difference calculation measures the duration between two calendar dates. Use it for deadlines, project schedules, age intervals, billing periods, study plans, maintenance windows, travel planning, and business-day estimates.

Formulas

Formulas used

Total days

total days = end date - start date

Inclusive days

inclusive days = total days + 1 when the end date is included

Business days

business days = weekdays between the two dates, excluding Saturday and Sunday

Worked example

Example calculation

Days between dates

From 2026-01-01 to 2026-01-31 is 30 days, or 31 days if the end date is included

Business days

The weekday count excludes Saturdays and Sundays for a quick workday estimate

Guide

How to use this calculator

  1. Enter the start date and end date.
  2. Use Include end date when the final date should count as part of the duration.
  3. Read total days for exact elapsed time and calendar duration for years, months, and days.
  4. Use business days for a simple Monday-to-Friday planning estimate.

Reference

What the results mean

Calendar duration

The difference expressed as complete years, months, and days.

Total days

The exact number of elapsed days between the dates.

Total weeks

Total days divided by seven.

Business days

Weekdays in the range, excluding Saturdays and Sundays.

Assumptions and limits

Before using the result

  • Business days exclude Saturdays and Sundays only; public holidays are not removed.
  • If Include end date is selected, one day is added to the total day count and the end date is included in the business-day count.
  • Contracts, payroll, legal deadlines, school terms, and project schedules may use their own date-counting rules.

FAQ

Date Difference Calculator questions

How do I calculate days between two dates?

Enter the start date and end date. The calculator subtracts the start date from the end date and shows total days, weeks, months, and calendar duration.

Should I include the end date?

Use Include end date when both the first and last dates count, such as a trip from Monday through Friday. Leave it off for elapsed time between dates.

Does the business days result include holidays?

No. It excludes Saturdays and Sundays only. Remove public holidays separately if your schedule requires them.

Related

General tools calculators