Pregnancy Due Date Calculator

Instant, accurate pregnancy due date calculations. Track trimester milestones week by week - medically-informed & private - plan your journey today!

How We Calculate Your Due Date

Our calculator uses Naegele's Rule, the standard method used by healthcare providers worldwide:

  1. Take the first day of your last menstrual period (LMP)
  2. Add 280 days (40 weeks or 9 months + 7 days)
  3. This assumes a 28-day cycle with ovulation on day 14

For irregular cycles, your healthcare provider may use an ultrasound measurement to confirm or adjust your due date.

Your Pregnancy Timeline

First Trimester (Weeks 1-13)

Key Developments: Major organs form, heart begins beating, brain develops rapidly

Common Symptoms: Morning sickness, fatigue, breast tenderness, frequent urination

Important Milestones: First prenatal visit, genetic screening options, first ultrasound (8-12 weeks)

Second Trimester (Weeks 14-27)

Key Developments: Baby can hear, movements felt, sex can be determined

Common Symptoms: Energy returns, "pregnancy glow", growing belly, backaches

Important Milestones: Anatomy scan (18-22 weeks), glucose screening (24-28 weeks), baby's first kicks

Third Trimester (Weeks 28-40)

Key Developments: Baby gains weight, lungs mature, moves into birth position

Common Symptoms: Braxton Hicks contractions, shortness of breath, swelling, nesting instinct

Important Milestones: Childbirth classes, hospital tour, pediatrician selection, delivery!

📅 Important Note

Only about 5% of babies arrive on their exact due date. Full-term pregnancy is 37-42 weeks. Your baby could arrive anytime in this healthy range.