Calculate the exact time between two dates in years, months, weeks, days, hours, and minutes, plus the number of business days (excluding weekends) between them. Includes one-click Today buttons for fast date entry.
This tool presents your date difference in two complementary formats: a calendar breakdown (years, months, and days, the way a person would naturally describe an age, a tenure, or a project length) and a fixed-unit breakdown (total weeks, days, hours, and minutes, useful when you need one consistent number for a calculation, spreadsheet formula, or comparison). Both describe the exact same underlying span between your two dates — they're just expressed in units suited to different purposes, and neither is more 'correct' than the other.
A naive date-difference calculation might simply divide total days by 365 to estimate years, but this introduces creeping inaccuracy because calendar years aren't uniformly 365 days (leap years add a 366th day roughly every four years) and calendar months range from 28 to 31 days. This tool instead performs a true calendar subtraction — counting whole years, then whole months within the remainder, then whole days within that remainder — which is the same method you'd use counting by hand on a physical calendar, and produces an exact, not approximate, breakdown.
A calendar day count treats every day identically, while a business day count specifically excludes Saturdays and Sundays, which matters whenever a task, payment term, or legal notice period is defined in 'business days' or 'working days' rather than calendar days — a common distinction in contracts, shipping estimates, and payroll processing. This tool's business day count follows the standard Monday-through-Friday definition; it does not currently account for public holidays or region-specific weekend conventions, so treat it as a baseline weekday count rather than a fully holiday-adjusted figure for your specific jurisdiction.
Date difference calculations come up constantly in everyday planning and professional work: estimating how much runway remains before a project deadline, calculating an employee's exact tenure for an anniversary, bonus, or benefits-eligibility milestone, figuring out a rental, lease, or subscription period's exact length, determining how many working days remain to complete a task when weekends don't count toward the schedule, and calculating age-like spans between any two events, not just a birth date and today (which is what a dedicated Age Calculator handles instead).
This calculator works with plain calendar dates and does not incorporate specific times of day, time zones, or region-specific public holidays into its business day count — it treats every non-weekend day as a working day regardless of national or regional holiday calendars. For most everyday planning purposes this level of precision is exactly right, but if your specific use case requires holiday-aware business day counting for a particular country, you'll need to manually subtract any holidays that fall within your date range from the business day figure this tool provides.
Date Difference Calculator measures the span between any two dates. These related tools handle other common date and time calculations.