Weeks From Today Calculator

Number of weeks

Direction

Starting date (optional)

First date

Second date

Your date is

Great for planning ahead from a due date, an ultrasound date, or any appointment — count forward for a target date, or count between two dates to see the gap in weeks and days.

How this is calculated

This tool does exact calendar-day arithmetic, not an average. Counting "6 weeks from today" simply means adding 42 real calendar days to your starting date and reading off the resulting date and weekday — it correctly accounts for how many days are actually in each month, and for leap years, rather than treating every month as the same length.

The "between two dates" mode works the same way in reverse: it finds the exact number of days between your two dates, then expresses that as whole weeks plus any leftover days, so you get both a tidy week count and the precise day total.

Common uses for this calculator

This kind of week counting comes up constantly in pregnancy planning: figuring out when you'll hit a specific week for a scan or screening, checking how far away a due date or appointment is, or working out what date a milestone (like "20 weeks" or "36 weeks") actually falls on. Many care providers schedule key visits — like the mid-pregnancy anatomy scan around 18–22 weeks, or glucose screening around 24–28 weeks — by week number rather than calendar date, so converting between the two is genuinely useful.

It's just as handy outside pregnancy contexts too — counting toward any appointment, deadline, or event a certain number of weeks out, or checking how many weeks have passed since something already happened, like a birth or a procedure.

Things to double-check

The "weeks from a date" mode defaults to counting from today if you leave the starting date blank, so double-check which date you actually want before relying on the result. When comparing two dates, the calculator reports the absolute gap regardless of which date comes first — so swapping the first and second date fields won't change the answer, only the "ahead"/"ago" framing changes when you use the single-date mode instead.

Because this counts real calendar days, results near the end of a month or across a leap year (like February 29) are handled automatically and correctly — there's no need to manually adjust for shorter months or leap years yourself.

Sources

General guidance on typical prenatal visit timing: American College of Obstetricians and Gynecologists (ACOG) · NHS.