Weeks Between Two Dates

Count the number of weeks (and leftover days) between any two dates.

Free weeks-between-dates calculator. Enter a start and end date to get the number of full weeks plus leftover days, exact decimal weeks and total days. Privacy-first — everything runs in your browser and nothing is sent anywhere. It runs free in your browser on Gera Tools, with nothing uploaded.

Last updated Source: Gera Tools

How do I count the number of weeks between two dates?

Subtract the earlier date from the later one to get total days, then divide by 7. The whole-number part is full weeks and the remainder is leftover days. This tool does all three for you automatically.

Weeks between two dates

This tool counts how many weeks separate any two dates, reporting the span three ways: as full weeks plus leftover days, as an exact decimal-week figure, and as a total day count. It is handy for pregnancy tracking, project timelines, notice periods, leave calculations, and counting down to a deadline.

How it works

Both dates are floored to local midnight, so the result never wobbles with the time of day. The tool then takes the absolute difference in days and divides by 7:

total days ÷ 7 = decimal weeks

The whole-number part is the count of full weeks, and the remainder is the leftover days. Because it uses the absolute difference, the order you enter the dates in does not matter — the answer is always positive. Leap years are handled automatically — any February 29 that falls within the range is counted as a normal day.

Worked example

From 1 January 2026 to 15 February 2026 is 45 days. Dividing by 7 gives 6 weeks and 3 days (6 × 7 = 42, with 3 days left over), or 6.43 weeks as a decimal.

Common use cases and what to enter

Pregnancy tracking: Enter the first day of the last menstrual period (LMP) as the start date and today as the end date. The result shows the current gestational week, which matches the week number used in prenatal appointments. A full-term pregnancy is 40 weeks (280 days) from LMP.

Notice periods: Employment contracts often specify weeks of notice. Enter the notice-start date and the proposed last day to verify the period meets the contract requirement.

Project sprint planning: Sprints are typically two-week cycles. Enter the project start and deadline to see how many full sprints fit, with any leftover days visible as the partial sprint.

Leave and holiday calculations: HR teams use week counts to validate annual leave bookings that span part-weeks. The “full weeks plus days” format matches most leave-policy language.

Counting down to an event: Enter today and the event date to see both the full weeks remaining and the exact decimal figure for planning progress milestones.

The three output formats explained

FormatExampleWhen to use it
Full weeks + days6 weeks 3 daysHuman-readable, matches contract/policy language
Decimal weeks6.43 weeksCalculations, progress percentages, charting
Total days45 daysThe underlying figure; useful for verifying manually

All three derive from the same day count — they are different ways of presenting the same measurement. Both dates stay in your browser and are never sent anywhere.