Days Between Dates Calculator

TL;DR

Compute days between two dates:

• inclusive (counts both endpoints)
• exclusive (difference without counting both endpoints)

Who this is for

• HR/admin tasks, notice periods, contract windows.
• Anyone needing quick date math.

How to use it

1. Pick start date and end date.
2. Choose the interpretation you need (inclusive vs exclusive).

Inclusive vs exclusive (the “off by one” problem)

This tool exists because people routinely disagree on what “between two dates” means.

Inclusive

Counts both endpoints. Example: from Jan 1 to Jan 1 is 1 day. Use inclusive when you’re counting “days covered” by a period.

Exclusive

Counts the gap between dates without counting both endpoints. Example: from Jan 1 to Jan 1 is 0 days. Use exclusive when you’re measuring “how much time passed between events”.

If you’re not sure, decide which answer feels correct for “same day” and you’ll usually pick the right mode.

Calendar days vs working days

This tool counts calendar days. If your next question is “how many working days is that?”, use Working days.

Many real-world rules are expressed as:

• calendar days (often in legal/notice contexts)
• working days / business days (often in delivery timelines and internal approvals)

Always confirm which one your scenario uses before you commit to a number.

Worked examples

Example 1: notice period sanity check

Compute the number of days between the notice start and notice end date.

Example 2: contract window

Compute exclusive days if your contract defines “between dates” without counting the first day.

Example 3: billing cycles

Use inclusive for “count both endpoints” periods, then decide whether weekends/holidays matter separately.

Example 4: content/calendar planning

If you plan “publish 10 posts over 30 days”, you usually care about the covered days (inclusive). If you measure “days since last update”, you usually care about the gap (exclusive).

Common scenarios (how people actually use this)

Notice / probation / contract windows

Teams often need a quick check for “how many days are between these dates?” before they draft or validate HR paperwork. The right choice (inclusive/exclusive) depends on the wording.

SLAs and response windows

If you promise a response “within 3 days”, clarify whether weekends count. This tool can give you the calendar-day number; working-day logic is a separate question.

Counting “days active” for subscriptions

When you track “active days” for access windows, inclusive counting is usually the correct mental model.

Gotchas

• If you care about working days use Working days.
• Public holidays are not excluded here; this tool is calendar-day math.
• If you need Romanian public holidays excluded, treat this as baseline and adjust manually.

FAQ

Which mode should I use for notice periods?

Some notice periods are defined in calendar days, some in working days, and the “inclusive/exclusive” interpretation can also be specified. When it’s contractual/legal, follow the text exactly.

Why do people disagree about this so often?

Because natural language is ambiguous: “between” can mean “gap” (exclusive) or “covered period” (inclusive). This tool makes the choice explicit so you don’t ship an off-by-one mistake into a contract or timeline.

What next?

Use Working days when the next question becomes “how many working days is that?”

Next steps (IT Jobs List)

For employment calculators, treat the result as guidance, not legal advice. Always verify your company policy/contract.

Related tools

• Working days

Related guides

• Working days in Romania: planning and estimation

Quick recommendation

• Save your assumptions (rates, breaks, thresholds) so you can reproduce the result.
• If you use the output in an invoice/offer, include a short explanation (what’s included and what’s not).

Practical checklist (IT Jobs List)

• Treat calculators as guidance and verify your contract/internal policy.
• Keep one computed example (with numbers) for discussions.
• If working days/holidays matter, clarify the exact period.