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Free pregnancy and baby tools

Calculators that run on your phone and send nothing anywhere, each with the official rule it uses.

Updated October 13, 2026 · sources checked October 13, 2026

In short

These calculators use the rules health professionals use: 280 days from your last period for the due date (ACOG), weeks counted from that same day, the NHS appointment schedule, a six-day fertile window ending on ovulation, NHS thresholds for contractions and the WHO advice to start solids at around 6 months.

Due date calculatorFree due date calculator using the method obstetricians use: last period (280 days), conception date, IVF transfer or ultrasound dating. Nothing is sent.How many weeks pregnant am I?Find out exactly how many weeks and days pregnant you are today, your trimester and the days left until your due date, from your last period or due date.Pregnancy calendar, week by weekYour pregnancy calendar from week 4 to week 42 with real dates, trimesters and the NHS antenatal appointment schedule, calculated from your period or due date.Ovulation calculatorEstimate your ovulation day and fertile window for your next three cycles from your last period and cycle length. Free, private, not a contraception method.Contraction timerFree contraction timer for your phone: one tap to start and stop, length and frequency over the last hour, and the NHS signs that mean calling now.Starting solids calendarEnter your baby's birth date to see when they reach about 6 months, the signs of readiness, allergens one at a time, and the 1-year milestones for milk and honey.Baby age calculatorHow old is your baby exactly? Enter the date of birth to see the age in weeks, months and days, and open the guide for that month.

Week by week

Month by month

Sources

  1. ACOG Committee Opinion No. 700, Methods for Estimating the Due Date (2017) checked October 13, 2026
  2. NHS — Signs that labour has begun checked October 13, 2026
  3. WHO — Infant and young child feeding (fact sheet) checked October 13, 2026

Mamavela explains; it does not replace your midwife, doctor or pediatrician, who know your situation. If something worries you, call them. In an emergency, call 911 (US), 999 (UK) or 112.