How Far Along Am I?

Pregnancy progress is measured in gestational age, counted from the first day of your last menstrual period (LMP) — not from the date you conceived. This calculator takes your LMP (or your due date, back-calculated to an LMP), subtracts it from today's date, and converts the number of days into completed weeks and days. So if you're '20 weeks and 3 days' along, that means 20 weeks and 3 days have passed since the first day of your LMP.

Doctors count gestational age from LMP because ovulation and conception dates are hard to pin down precisely, while the start of a period is a clear, memorable reference point. Since ovulation typically happens about two weeks after the LMP, gestational age runs roughly two weeks ahead of your baby's actual developmental (conceptional) age. In other words, at '6 weeks pregnant,' your baby has usually only been developing for about 4 weeks since conception.

Baby size comparisons (like 'the size of a papaya') are approximate averages based on typical fetal length and weight at each gestational week — they give a fun, intuitive sense of growth rather than a precise measurement. Every pregnancy is different, and actual size can vary. Ultrasound measurements from your healthcare provider are the accurate way to track your specific baby's growth.

If you only know your due date, this calculator can back-calculate your estimated LMP by subtracting 280 days (40 weeks) from it, then use that date to determine your current week and day of pregnancy. Just switch to the 'I know my due date' mode and enter the date your provider gave you.

Pregnancy is divided into three trimesters: the first trimester runs from week 1 through week 12, the second trimester spans weeks 13 through 27, and the third trimester covers weeks 28 through 40 (and beyond, if you go past your due date). This calculator automatically shows which trimester you're currently in based on your gestational age.

A due date is a statistical estimate, not a guarantee — only about 4–5% of babies are born on their exact due date. Most births happen within a window of about two weeks before or after the estimated date, and a full-term pregnancy is generally considered anywhere from 37 to 42 weeks. If you go past 40 weeks, your calculator will simply show a negative countdown and mark your status as 'past due,' which is common and not unusual on its own — talk to your provider about monitoring options.

Yes. When your doctor or midwife says you're '24 weeks' or '24 and 3,' they mean gestational age counted from your LMP, exactly like this calculator. If an early ultrasound suggested a slightly different due date than the one calculated from your LMP, your provider may use the ultrasound-based dating instead — in that case, use the 'I know my due date' mode with that adjusted date for the most accurate results.