Date Midpoint Calculator

Find the exact halfway point between two dates or date-times, see both center-date candidates when the midpoint lands at noon, split the span into equal parts, add custom percentage checkpoints, and export a reproducible timeline.

Halfway date · exact time · equal parts

Date Midpoint Calculator

Enter two dates and get the exact halfway point instantly. Turn on time only when hour-and-minute precision matters.

Runs in your browser

Include time

Start date End date

Exact midpoint

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—elapsed span

—each half

—midpoint weekday

—calendar-day count

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Split the span evenly

Useful for project checkpoints, payment milestones, trips, or any evenly spaced schedule.

Equal parts

Boundary	Date / time	From start	Remaining

More date tools

Average multiple dates

Paste one ISO date per line. The mean is calculated from timestamps, not from month numbers.

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Counting conventions

Elapsed days count 24-hour boundaries between date-only inputs.
Inclusive calendar count includes both endpoint dates.
Date-only math uses midnight UTC so daylight-saving transitions cannot create 23/25-hour surprises.
This tool does not remove weekends or holidays. Use a business-day calculator when workday rules matter.

How the midpoint is calculated

midpoint = earlier instant + (later instant − earlier instant) ÷ 2. If a date-only span contains an odd number of days, the exact middle lands at 12:00 rather than on a midnight boundary. This calculator shows that exact half-day instead of silently rounding to a neighboring date.

Calendar date or elapsed-time midpoint?

The exact midpoint is always an elapsed-time calculation. The ambiguity appears only when you insist on displaying that instant as one whole calendar date. Date-only mode makes that distinction visible instead of silently rounding it away.

Worked check

January 1 at 00:00 UTC to January 4 at 00:00 UTC spans exactly 3 days. The exact midpoint is January 2 at 12:00 UTC. If your workflow requires one whole-date label, January 2 and January 3 are the adjacent midnight candidates and the selected rounding policy decides which label to display.

Verification: subtract the earlier instant from the midpoint and the midpoint from the later instant. Those elapsed durations must be identical even when the displayed whole-date labels are not.

Why UTC serials are used for date-only mode

A pure calendar date has no time zone. Mapping each date to midnight UTC creates a stable integer-day axis, so daylight-saving transitions cannot turn a nominal one-day step into 23 or 25 hours. Date-time mode remains separate because clock-time inputs really do have zone semantics.

Planning beyond 50%

Equal-part boundaries and custom percentage checkpoints let the same span produce quarter reviews, thirds, payment stages or other elapsed-time milestones. These are not holiday-aware business-day calculations.