Calculate your pregnancy due date and track your baby’s development week by week. Simply enter your last menstrual period (LMP) date or conception date to get your estimated due date, current pregnancy week, and trimester information.
While only about 5% of babies arrive exactly on their due date, knowing your estimated delivery date helps you and your healthcare provider plan important prenatal visits, tests, and prepare for your baby’s arrival.
Pregnancy Due Date Calculator
Estimate Your Baby's Arrival Date & Track Your Pregnancy Journey
All calculations happen in your browser. Your information is never stored or transmitted.
Calculate Your Due Date
Choose your preferred calculation method and enter the relevant date to estimate your baby's due date.
First Trimester (Weeks 1-13)
The first trimester is a period of remarkable development. By week 4, the neural tube (future brain and spinal cord) begins forming. By week 8, all major organs have started developing, and the embryo is now called a fetus. By week 12, the fetus is about 2.5 inches long with fully formed fingers and toes.
Common Symptoms
- Morning sickness (can occur any time of day, typically peaks weeks 8-10)
- Extreme fatigue as your body increases blood production by up to 50%
- Breast tenderness and swelling
- Frequent urination as the uterus presses on the bladder
- Food aversions and heightened sense of smell
Important Appointments
- Week 8-10: First prenatal visit — blood work, health history, dating ultrasound
- Week 10-13: Optional first-trimester screening (nuchal translucency ultrasound + blood tests)
- Begin taking prenatal vitamins with folic acid (ideally started before conception)
Second Trimester (Weeks 14-27)
Often called the "golden trimester" as many uncomfortable first-trimester symptoms subside. By week 16, the baby starts developing hearing. By week 20, you may feel the first movements ("quickening"). By week 24, the baby reaches viability — the lungs begin producing surfactant.
Common Experiences
- Increased energy levels and reduced nausea
- Visible baby bump developing
- First fetal movements felt (typically weeks 18-22)
- Mild swelling in feet and ankles
- Backaches as your center of gravity shifts
Important Appointments
- Week 18-22: Anatomy scan (detailed ultrasound to check all organ systems)
- Week 24-28: Glucose tolerance test for gestational diabetes screening
- Regular prenatal visits every 4 weeks
Third Trimester (Weeks 28-40)
The final stretch! The baby gains about half a pound per week. By week 32, bones are fully formed but still soft. By week 36, the baby typically moves into a head-down position. By week 37, pregnancy is considered full-term.
Common Experiences
- Braxton Hicks contractions (practice contractions)
- Increased fatigue and difficulty sleeping
- Shortness of breath as the baby presses on your diaphragm
- Frequent urination returns as the baby descends
- "Nesting instinct" — strong urge to prepare baby's space
Important Preparations
- Week 28+: Prenatal visits every 2 weeks, then weekly from week 36
- Week 36: GBS (Group B Streptococcus) screening
- Prepare hospital bag, birth plan, and infant car seat
- Learn signs of labor vs. false labor
Pregnancy Nutrition Guide
Proper nutrition during pregnancy supports both your health and your baby's development. You need approximately 340 extra calories/day in the second trimester and 450 extra/day in the third trimester.
Essential Nutrients
- Folic acid (600mcg/day): Prevents neural tube defects. Found in leafy greens, fortified cereals, lentils
- Iron (27mg/day): Supports increased blood volume. Found in lean meats, spinach, fortified grains
- Calcium (1000mg/day): Builds baby's bones and teeth. Found in dairy, fortified plant milks, tofu
- DHA omega-3: Supports brain and eye development. Found in fatty fish, walnuts, DHA supplements
- Vitamin D (600 IU/day): Helps calcium absorption. Found in fortified milk, sunlight, supplements
Foods to Avoid
- Raw or undercooked meats, fish, and eggs (risk of toxoplasmosis, listeria, salmonella)
- High-mercury fish (shark, swordfish, king mackerel, tilefish)
- Unpasteurized dairy and soft cheeses
- Excessive caffeine (limit to 200mg/day — about one 12oz coffee)
- Alcohol — no amount is proven safe during pregnancy
Warning Signs: When to Call Your Provider
🚨 Seek Immediate Care
- Heavy vaginal bleeding (soaking a pad in less than an hour)
- Severe abdominal pain or cramping
- Severe headache with vision changes or facial swelling (signs of preeclampsia)
- Fever above 100.4°F (38°C)
- Sudden gush of fluid from vagina (possible membrane rupture)
- Baby's movements significantly decrease or stop (after 28 weeks)
Contact Your Provider Soon
- Persistent vomiting preventing you from keeping fluids down
- Painful or burning urination (possible UTI)
- Unusual vaginal discharge
- Regular contractions before 37 weeks
- Persistent headaches, swelling in hands/face, or vision changes
Frequently Asked Questions
Due date calculators provide an estimate based on average pregnancy length (280 days from LMP). Only about 5% of babies arrive on their exact due date. Most births occur within 2 weeks before or after the estimated date. First-trimester ultrasound dating is generally the most accurate method, with accuracy within 5-7 days.
First-trimester ultrasound (before 13 weeks) is considered the most accurate dating method because early fetal growth is very consistent. The LMP method assumes a 28-day cycle with ovulation on day 14, which varies among women. If your LMP date and ultrasound dating differ by more than 7 days in the first trimester, providers typically use the ultrasound date.
Our calculator adjusts for cycle length. With a longer cycle (e.g., 35 days), ovulation likely occurred later, so your due date shifts forward. With a shorter cycle (e.g., 24 days), ovulation was earlier, and your due date shifts back. This adjustment accounts for the difference between cycle length and the standard 28-day assumption.
According to ACOG, full-term is defined as 39 weeks 0 days through 40 weeks 6 days. Early term is 37-38 weeks, late term is 41 weeks, and post-term is 42 weeks or later. Babies born at 37+ weeks generally do well, but those born at 39+ weeks have the best outcomes for lung maturity, brain development, and birth weight.
Yes. Your provider may adjust your due date based on first-trimester ultrasound measurements. This happens when ultrasound dating differs significantly from LMP-based calculations. Once established, however, the due date should not change based on later ultrasounds, as growth variability increases as pregnancy progresses.
For most healthy pregnancies, ACOG recommends 150 minutes of moderate-intensity aerobic activity per week. Safe activities include walking, swimming, stationary cycling, and prenatal yoga. Avoid contact sports, activities with fall risk, exercises lying flat on your back after the first trimester, and hot yoga/hot tubs. Always discuss your exercise plan with your provider.
Medical Disclaimer
This pregnancy due date calculator provides an estimate based on standard obstetric calculations. Only about 5% of babies arrive on their exact due date, and individual pregnancies vary. Your healthcare provider will determine the most accurate due date based on your complete medical information, including ultrasound measurements. This tool is for educational purposes and does not replace professional prenatal care.
Clinical References
- American College of Obstetricians and Gynecologists (ACOG). Methods for Estimating the Due Date. Committee Opinion No. 700. Obstet Gynecol. 2017;129:e150-e154.
- ACOG. Definition of Term Pregnancy. Committee Opinion No. 579. Obstet Gynecol. 2013;122:1139-1140.
- Naegele FC. Lehrbuch der Geburtshilfe. 1830. (Naegele's Rule for EDD calculation).
- ACOG. Nutrition During Pregnancy. FAQ001. acog.org
- March of Dimes. Prenatal Care Checkups. marchofdimes.org