Estimate your baby’s due date from the first day of your last period, your conception date or an ultrasound dating scan. You can also see which trimester you are in and view a week-by-week timeline and planning checklists.
Pregnancy Progress
Important Dates
| Milestone | Date | Week |
|---|
About Your Baby This Week
Understanding Due Dates
Your due date is an estimate of when your baby will be born, calculated as 40 weeks (280 days) from the first day of your last menstrual period. Keep in mind:
- Only about 5% of babies are born on their exact due date
- Most babies arrive between 37-42 weeks
- First-time mothers often deliver slightly later (40 weeks 5 days on average)
- Your healthcare provider may adjust your due date based on ultrasound measurements
- Early ultrasounds (before 13 weeks) are the most accurate for dating
First Trimester
Key Developments:
- Baby’s organs begin forming
- Heart starts beating (week 6)
- Fingers and toes develop
- All major organs present by week 12
Common Symptoms:
- Morning sickness
- Fatigue
- Breast tenderness
- Frequent urination
Second Trimester
Key Developments:
- Baby’s movements felt (quickening)
- Sex can be determined
- Hair and eyebrows develop
- Rapid brain development
Common Symptoms:
- Growing belly
- Increased energy
- Back pain
- Heartburn
Third Trimester
Key Developments:
- Eyes open and close
- Lungs mature
- Baby gains weight rapidly
- Settles into head-down position
Common Symptoms:
- Shortness of breath
- Swelling in feet/ankles
- Braxton Hicks contractions
- Difficulty sleeping
| Week | Date | Baby Size | Key Development |
|---|
Prenatal Appointments Schedule
- Weeks 4-8: First prenatal visit – confirmation, due date, general health assessment
- Weeks 10-13: First trimester screening, possible nuchal translucency scan
- Weeks 16-20: Anatomy scan (20-week ultrasound), gender reveal possible
- Weeks 24-28: Glucose screening test for gestational diabetes
- Week 28: Rh antibody screening if Rh-negative
- Weeks 35-37: Group B strep test
- Weeks 36-40: Weekly check-ups, cervical checks
Tests & Screenings Timeline
Your Pregnancy To-Do List
First Trimester Checklist
Second Trimester Checklist
Third Trimester Checklist
Nutrition Guidelines During Pregnancy
- Folic Acid: 400-800 mcg daily (prevents neural tube defects)
- Iron: 27 mg daily (prevents anemia)
- Calcium: 1000 mg daily (bone development)
- Protein: 75-100g daily (tissue growth)
- DHA: 200-300 mg daily (brain development)
- Water: 8-10 glasses daily (hydration)
Foods to Avoid:
- Raw or undercooked meat, poultry, seafood
- Unpasteurized dairy products
- High-mercury fish (shark, swordfish, king mackerel)
- Raw eggs and foods containing them
- Deli meats and hot dogs (unless heated)
- Alcohol and limit caffeine (less than 200mg/day)
Exercise During Pregnancy
Safe exercises include walking, swimming, prenatal yoga, and light strength training. Aim for 30 minutes of moderate activity most days.
- Listen to your body and don’t overexert
- Stay hydrated and avoid overheating
- Avoid contact sports and activities with fall risk
- Don’t lie flat on your back after 20 weeks
- Stop if you experience pain, dizziness, or bleeding
Hospital Bag Essentials
For Mom:
- Insurance card and ID
- Birth plan (if you have one)
- Comfortable going-home outfit
- Toiletries and personal items
- Comfortable slippers or socks
- Nursing bras and pads
- Phone charger
For Baby:
- Going-home outfit (newborn and 0-3 month sizes)
- Blankets for warmth
- Car seat (properly installed)
- Diapers and wipes (hospital usually provides)
- Pacifiers if desired
Signs of Labor
Call your healthcare provider if you experience:
- Regular contractions: 5-10 minutes apart for an hour
- Water breaking: Gush or trickle of fluid
- Bloody show: Mucus plug with blood
- Severe back pain: Constant or with contractions
Go to hospital immediately if:
- Vaginal bleeding (more than spotting)
- Severe abdominal pain
- Decreased fetal movement
- Severe headache with vision changes
- Sudden swelling of face, hands, or feet
What this due date calculator does
- Due Date Calculator: works out the due date, current week and day, trimester, days remaining and key dates using the method you choose.
- Pregnancy Timeline: shows your due date, conception estimate, the three trimesters and a week-by-week overview.
- Complete Planner: adds to-do timelines and checklists for each trimester.
How the due date is calculated
- Last menstrual period (LMP): due date = first day of your last period + 280 days (40 weeks). If your cycle is not 28 days, the calculator adds or subtracts the difference.
- Conception date: due date = conception date + 266 days (38 weeks).
- Ultrasound: due date = scan date + (280 days minus the gestational age at the scan).
Worked example: a last period starting on 15 January 2026 gives a due date of 22 October 2026. A conception date of 29 January 2026, or an ultrasound on 12 March 2026 measuring 8 weeks 0 days, gives the same date.
Health professionals use the last period and an early ultrasound to date a pregnancy; see the American College of Obstetricians and Gynecologists guidance (Committee Opinion 700, Methods for Estimating the Due Date).
Things to keep in mind
Only a small share of babies arrive on the exact due date, so think of it as the centre of a window. Your doctor or midwife will confirm or adjust your due date, usually using an early ultrasound. The week-by-week descriptions and checklists are general information, not medical advice. This calculator is for general information only and is not medical advice. If you have questions about your result, talk with your health care provider.
Frequently asked questions
Which method is most accurate?
Clinicians generally rely on an early ultrasound together with your last period. If your own estimate and your scan disagree, follow your care provider’s date.
Is my information stored?
The dates you enter are used only in your browser to show the results and are not sent to this website.
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