Pregnancy Calculator - Due Date Calculator
Calculate your due date, current pregnancy week, and track your pregnancy journey
What is a Pregnancy Calculator? Understanding Due Date Calculation
A pregnancy calculator is an essential tool that helps expectant mothers determine their due date and track their pregnancy progress. This pregnancy due date calculator uses your last menstrual period (LMP), conception date, or ultrasound information to provide accurate estimates of when your baby is expected to arrive.
The standard pregnancy duration is 280 days (40 weeks) from the first day of your last menstrual period. Our due date calculator accounts for different cycle lengths and calculation methods to give you the most accurate results possible. Track your baby's growth weekly with detailed information about each stage of pregnancy development.
Pregnancy Due Date Calculation Methods
This pregnancy week calculator method assumes a 28-day cycle with ovulation on day 14. Most accurate for women with regular cycles.
Conception Date Method: If you know when conception occurred, add 266 days for your due date calculation
Ultrasound Method: Uses fetal measurements to determine gestational age and due date with high accuracy
IVF Method: For in vitro fertilization, calculate from embryo transfer date plus specific days based on embryo stage
Irregular Cycles: Women with irregular periods may need ultrasound confirmation for accurate dating
Pregnancy Trimesters and Baby Growth Weekly Tracker
Week 4-6: Heart begins beating, neural tube forms
Week 8: All major organs present, limbs develop
Week 10: Baby officially called a fetus
Week 12: Reflexes develop, gender formation begins
Common Symptoms: Morning sickness, fatigue, breast tenderness
Use our pregnancy tracker to monitor your baby's weekly development milestones.
Week 16: Gender can be determined via ultrasound
Week 18-20: Anatomy scan, movement felt
Week 22: Hearing develops, hair and nails grow
Week 24: Viability milestone reached
Common Changes: Visible bump, increased energy, baby kicks
The "golden period" of pregnancy with reduced symptoms and increased comfort.
Week 28: Eyes open, rapid brain development
Week 32: Bones harden, fat accumulates
Week 36: Lungs mature, baby considered full-term
Week 37-40: Ready for birth, head-down position
Preparation Phase: Braxton Hicks contractions, nesting instinct
Final preparations for delivery with weekly monitoring becoming more frequent.
Baby Size Comparison Chart - Weekly Growth Tracker
Our pregnancy calculator provides weekly size comparisons to help visualize your baby's growth journey.
Pregnancy Health Tips and Weekly Care Guide
- • Regular Check-ups: Follow your doctor's appointment schedule for optimal monitoring
- • Prenatal Vitamins: Take folic acid and prenatal supplements as recommended
- • Healthy Diet: Focus on nutrient-rich foods, avoid harmful substances
- • Exercise: Maintain safe, moderate exercise routine approved by your doctor
- • Hydration: Drink plenty of water throughout your pregnancy journey
- • Sleep: Prioritize adequate rest and comfortable sleeping positions
- • Alcohol & Smoking: Completely avoid alcohol and tobacco products
- • Raw Foods: Avoid raw fish, meat, eggs, and unpasteurized products
- • High Mercury Fish: Limit consumption of certain fish types
- • Excessive Caffeine: Limit coffee and caffeinated beverages
- • Certain Medications: Consult doctor before taking any medications
- • Stress: Manage stress levels through relaxation techniques
Frequently Asked Questions About Pregnancy Due Date Calculator
A pregnancy due date calculator provides an estimate with about 80% accuracy within 2 weeks of the predicted date. Only about 5% of babies are born exactly on their due date. The accuracy depends on having regular menstrual cycles and knowing the exact date of your last period. Our pregnancy calculator uses the standard Naegele's rule, which adds 280 days to your last menstrual period. For irregular cycles, ultrasound dating may be more accurate.
You can start using a pregnancy week calculator as soon as you know you're pregnant. Many women begin tracking around 4-6 weeks when they miss their period and get a positive pregnancy test. Early calculation helps you prepare for prenatal appointments, understand your baby's development stages, and plan for important milestones throughout your pregnancy journey.
Gestational age is calculated from your last menstrual period and is used by healthcare providers as the standard measurement. Fetal age (or conception age) is calculated from the actual conception date and is about 2 weeks less than gestational age. Our due date calculator uses gestational age, which is the medical standard for tracking pregnancy progress and scheduling prenatal care.
Yes! Our pregnancy tracker provides detailed weekly information about your baby's development, including size comparisons, developmental milestones, and what to expect each week. You can track your baby's growth from the size of a raspberry to a full-term baby, along with important developmental stages like when the heart starts beating, when movement begins, and when organs develop.
If you have irregular periods, a pregnancy calculator based on your last menstrual period may be less accurate. In this case, your healthcare provider may use ultrasound dating for more precise results. Our calculator includes options for different cycle lengths and calculation methods. For the most accurate dating with irregular cycles, early ultrasound measurements (between 8-13 weeks) are recommended.
Related Pregnancy and Health Calculators
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Calculate Weight GainEstimate when conception occurred based on your due date
Calculate ConceptionCheck your pre-pregnancy BMI for healthy weight management
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