Days Between Dates Calculator

When this calculator helps

Counting the days between two dates looks trivial until the answer really has to be right. Use this calculator when a deadline, a contract date, or a personal milestone depends on the figure — working out how many days until a lease ends, how long is left on a notice period, the full span of a project from start to delivery, or simply how many days old someone is. It is the everyday tool for any 'how long between' question across the euro area.

It is most valuable for the calculations that are awkward to do in your head, where months of different lengths and leap years get in the way. Whether you are counting down to an anniversary, measuring the gap between an invoice date and the day you were paid, or pinning down the exact length of a fixed-term agreement, you enter a start date and an end date and read off the days, weeks, and a calendar breakdown.

How to read your result

The headline figure is the number of days between your two dates — the calendar gap, not a count of the dates themselves. This is exclusive counting: the start date is day zero and the count moves on once you reach the next day, so 1 January to 2 January gives 1 day, not 2. That matches how interest, notice, and most contractual periods are reckoned across Europe.

If you need both endpoints counted instead — the inclusive total, which is what you want for something like rental days or a trip where you count both the day you arrive and the day you leave — add one to the figure shown. Knowing which version you need is the single most important part of reading the result, because the two always differ by exactly one day and it is easy to land on the wrong side of it.

A worked example

Suppose a fixed-term rental runs from 01/02/2026 to 01/08/2026 and you want the exact number of days. Enter 01/02/2026 as the start and 01/08/2026 as the end, and the calculator returns 181 days — about 26 weeks, or six calendar months in the Y/M/D breakdown. Because 2026 is not a leap year, the span contains no 29 February, so the day count and the calendar breakdown sit neatly together.

Now say you want the days remaining in a month, from 15/02/2026 to 28/02/2026. That comes out as 13 days. Had 2026 been a leap year, the same end-of-month count would reach 29 February and give 14. If you also meant to count the 15th itself, you would add one.

Common mistakes to avoid

Most date-counting errors are off-by-one slips or quietly mixing up which date came first.

• Confusing inclusive and exclusive counting — decide up front whether both endpoints should be counted, and add one if they should.
• Forgetting that February has 29 days in a leap year, which silently adds a day to any span crossing 29 February.
• Entering the dates in the wrong order; the day count is the same either way, but a swapped pair can hide a genuine input mistake.
• Reading the approximate-months figure as if it were exact calendar months — they only line up when both dates fall on the same day of the month.

Date formats across Europe

Most of Europe writes dates day-first: DD/MM/YYYY, so 03/04/2026 means the 3rd of April, not the 4th of March. The trouble starts when a date meets a US-based system or contact, where 03/04/2026 is read as March the 4th — a full month adrift. To sidestep the ambiguity, much of European business, and the Nordic countries in particular, lean on the ISO 8601 form, YYYY-MM-DD, which sorts cleanly and reads the same to everyone. When in doubt, spell out the month or use the ISO format so both sides are counting from the same day.

Day counting for contracts and notice periods is generally exclusive of the start date across the euro area, which is why this calculator's default gap matches the way most agreements are worded. Where a deadline must land on a working day, pair this with the Working Days Calculator to skip weekends and the public holidays that vary from one member state to the next.