What this calculator does
Time between dates is a broader question than a simple day count: it asks for the gap expressed the way people actually talk about it, in years, months and days together, alongside the same span restated as total days, weeks, hours and business days.
This calculator takes any two dates in either order and works out both the natural-language breakdown and the raw totals in one go, which is the form the figure usually needs to take for a report, a contract clause or a length-of-time question that a plain day count alone does not answer.
The formula
Years, months and days are counted forward from the earlier date to the later one, carrying across month and year boundaries the way a calendar would. The same span is then also given in total days, weeks and hours, and as a count of weekdays only.
| Term | Meaning |
|---|---|
| Earlier date | The starting point of the span being measured. |
| Later date | The end point of the span being measured. |
| Breakdown | The gap expressed as whole years, months and days, carried forward from the earlier date. |
| Business days | The count of weekdays only within the span, excluding Saturdays and Sundays. |
The inputs explained
| Field | What to enter |
|---|---|
| Earlier date | The earlier of the two dates. If entered later than the second date, the two are swapped automatically. |
| Later date | The later of the two dates. |
When to use it
Reporting a length of time in a business context
A contract term, a project duration or a length-of-service figure is usually expressed in years and months rather than a raw day count, which is what the breakdown gives directly.
Comparing the calendar breakdown against total days
Some uses need the natural years-months-days phrasing, others need a single number of days or hours; having both from the same calculation avoids running the numbers twice and risking a mismatch.
Counting only working time within a span
A project timeline or billing period often cares about business days specifically, separate from the calendar length of the span as a whole.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the years, months and days breakdown grows as the later date moves further out
A fixed earlier date of 1 January, measured against a series of later dates through the year and beyond.
| Later date | Breakdown | Total days | Business days |
|---|---|---|---|
| 2026-03-01 | 0 years, 2 months, 0 days | 59 | 41 |
| 2026-06-01 | 0 years, 5 months, 0 days | 151 | 106 |
| 2026-09-01 | 0 years, 8 months, 0 days | 243 | 172 |
| 2026-12-01 | 0 years, 11 months, 0 days | 334 | 238 |
| 2027-06-01 | 1 years, 5 months, 0 days | 516 | 367 |
| 2028-01-01 | 2 years, 0 months, 0 days | 730 | 521 |
Questions
How is this different from a plain days between dates calculator?
A plain day count gives one number. This calculator gives the same span as a years, months and days breakdown, plus total weeks, hours and business days, which is the fuller form most length-of-time questions actually need.
Does it matter which date I enter first?
No. If the earlier date is entered second, the two are swapped automatically before the calculation runs, so the result always reads forward in time.
Why do business days come out lower than total days divided by 7 times 5?
Business days are counted exactly, day by day, rather than estimated from a ratio, so the figure reflects the actual weekdays and weekend days that fall within the specific span entered rather than an average.
Can I use this to work out someone’s age?
It works for the same maths, but the how old am I calculator and the age calculator are built specifically for age, including the next birthday countdown.
For a simpler exclusive or inclusive day count only, see the days calculator. To count only weekdays, less any public holidays, use the working days calculator.