Pregnancy & baby

Your chances of conceiving are highest on a handful of days: the five days before ovulation and ovulation day itself. The period calculator works out your average cycle from your log, predicts your next six periods and fertile windows, and flags cycles that vary a lot. The ovulation calculator goes into the fertile window in more detail.

If your period is late, the pregnancy test timer shows your earliest and most reliable test day, and for IVF, when your beta-hCG blood test is likely. Once you have two hCG results, the hCG calculator works out the doubling time; your doctor is the one who interprets it.

It's a good idea to start taking 400 micrograms of folic acid a day at least a month before you try to conceive, and to go over any regular medications with your doctor.

The due date calculator works out your due date from your last period, conception date, IVF transfer or an ultrasound measurement, and tells you how far along you are. Our week-by-week pages cover each week: how big your baby is, what's changing in your body and which appointments are coming up.

The prenatal visit schedule lays out typical checkups and tests in order, based on ACOG and NICE guidance: ultrasounds, glucose screening and the group B strep test. The pregnancy weight gain calculator shows a target range matched to your pre-pregnancy BMI, following the National Academies guidelines.

In the third trimester, the kick counter and contraction timer can help, but for anything worrying, like fewer movements, bleeding, leaking fluid or a severe headache, don't rely on a calculator: call your provider or labor and delivery.

In the first year, tracking growth matters most. The baby percentile calculator uses the WHO growth standards, which the CDC recommends for children under 2, to show where your baby's weight, length and head size fall. The baby tracker logs feeds, sleep and measurements, all in your own browser.

The baby sleep schedule suggests wake windows and total sleep by age, and the milestones checklist, based on CDC and WHO lists, helps you know what to watch for. The teething chart shows when teeth usually come in. For vaccines, follow the schedule from your pediatrician and the CDC.

Percentiles aren't a contest: most healthy babies follow their own curve. If your baby suddenly crosses two percentile lines, isn't feeding, has few wet diapers or has a fever, call your pediatrician right away.

Every pregnancy and baby tool lists its sources, mainly official health organizations (WHO, CDC, NIH MedlinePlus, ACOG, NHS) and peer-reviewed research. We check formulas against known test cases, automatically for our new calculators before every release, and every page shows when it was last reviewed. Reviews are currently done by our editorial team; we don't list a named medical reviewer, because we don't have one yet.

The tools are for information only. They don't diagnose anything and don't replace your OB-GYN, midwife or pediatrician. Nothing you enter is uploaded. Anything that's kept, like your cycle log or baby tracker, stays in your own browser and can be deleted any time. Our editorial policy explains how we work and how to report a mistake.

Use the calculators to plan and prepare, and call your provider whenever something feels wrong. During pregnancy, get care right away for vaginal bleeding, severe belly pain, leaking fluid, a severe headache or vision changes, swelling of the face or hands, fever, or if your baby is moving less than usual. With a newborn, call for a fever of 100.4 °F (38 °C) or higher in a baby under 3 months, trouble breathing, poor feeding, fewer wet diapers or unusual sleepiness. In an emergency, call 911.