Days Between Two Dates

What the days between two dates tool does

How many days are there between two dates? It sounds like the simplest question in this whole category, and the arithmetic is, but there is a small twist in it that this tool handles for you. Give it a start date and an end date and it tells you how many days lie between them, and it also tells you how many of those are workdays, the weekdays only.

The twist is whether the last day counts, and the tool gives you a switch for it, because the right answer genuinely depends on what you are measuring.

How to use it

1. Start Date. The earlier date.
2. End Date. The later date.
3. Include Last Day. Choose No for the plain gap between the dates, or Yes to count the end date itself as one of the days. The next section explains which you want.

Press Calculate, and the day count appears, with the workdays underneath.

How the count is worked out

At heart it takes the end date away from the start date to find the gap in days. If you choose to include the last day, it simply adds one to that gap, so the end date is counted as a day in its own right. For the workdays figure it walks through the range day by day and counts only the ones that fall Monday to Friday, leaving out every Saturday and Sunday.

The include-last-day question, and the off-by-one trap

This is the part worth slowing down for, because it is where people land a day out without noticing. There is a nice everyday way to feel the difference. "See you in two days" is not the same as "see you tomorrow," even though only one day separates the two phrases, and that extra day is exactly what the include-last-day switch controls.

Leave it on No and you get the plain gap, the number of days from one date to the other. Switch it to Yes and the end date is counted too. Think of a hotel booking. If you check in on the 1st and check out on the 3rd, the gap is 2 days, which is your 2 nights, but the booking touches 3 calendar dates. Both numbers are correct, they just answer different questions. So when a count looks one off from what you expected, this switch is almost always the reason. A quick habit is to ask yourself plainly: am I measuring the gap between the dates, or counting every date involved?

An example with real numbers

Take 1 March to 15 March.

• With Include Last Day set to No, the gap is 15 minus 1, which is 14 days.
• With it set to Yes, the 15th counts too, so the answer is 15 days.

Fourteen for the gap, fifteen if both ends count. Neither is more correct than the other. A countdown to the 15th wants 14, while counting how many dates your plans cover wants 15.

The workdays figure

Underneath the day count, the tool also shows how many of the days are workdays, meaning Monday to Friday, with the weekends taken out. It is a quick way to get a rough sense of the working time in a span. One honest note though: it removes weekends only, not public holidays, since those change from country to country. If your range covers a holiday or two, take them off yourself. For working-day planning where you also want to add working days to a date, the dedicated business days calculator is the better tool.

Questions people ask

Does it count both the start and end date?

By default, no. You get the plain gap between the dates, which does not count the end date as an extra day. Switch Include Last Day to Yes when you want the end date counted too, such as for a stay or a booking.

Why is my answer one different from what I expected?

Almost always the include-last-day setting. Counting the gap and counting every date involved differ by exactly one, so check which one your situation needs.

What counts as a workday here?

Any day from Monday to Friday. The workdays figure leaves out Saturdays and Sundays, but it does not know about public holidays, so subtract those yourself if your range includes any.

Can I use this for a legal deadline?

For a rough count, yes, but legal and official deadlines often follow their own counting rules about which day starts the clock and how holidays are treated. For anything where the date really matters, check the specific rules that apply.