Pregnancy Calculator
Accurately estimate your due date, track your pregnancy progress, and learn about the changes happening to you and your baby with our comprehensive pregnancy calculator.
Calculate Your Due Date
Calculation Method
Select your preferred calculation method
The first day of your last menstrual period
Typical cycle length ranges from 21 to 45 days
Your Pregnancy Results
Estimated Due Date
April 15, 2026
Based on your last menstrual period and cycle length
Current Week
12
of 40 weeks
Days Pregnant
84
approx.
Estimated Delivery
216
days remaining
Trimester Progress
Current Trimester: Second Trimester
Baby Development at Week 12
First TrimesterSize: About 2.1 inches (5.4 cm) and weighs about 0.5 ounces (14 grams)
Development: Your baby's fingers and toes are fully formed. The kidneys are starting to produce urine, and the liver is making bile. The baby's bones are beginning to harden.
What to expect: You may start to feel more energetic as the first trimester fatigue fades. Some women begin to show a small baby bump this week.
Pregnancy Timeline
First Trimester (Weeks 1-12)
Your pregnancy officially starts on the first day of your last menstrual period. Ovulation typically occurs around day 14.
The fertilized egg implants into the uterine lining. Hormone levels rise, triggering early pregnancy symptoms.
Your baby is now called a fetus. Major organs begin to form, and the heart is fully developed.
The risk of miscarriage drops significantly. Your baby's vital organs are formed but not fully functional.
Milestones
You may start feeling fetal movement. The baby's sex can often be determined by ultrasound.
You'll likely feel your baby's first movements. The baby is covered in vernix caseosa to protect the skin.
Your baby's brain is rapidly developing. You may need to start prenatal classes.
Your baby is considered full term and could arrive at any time.
Pregnancy FAQs
How accurate is the due date calculator?
The due date calculated using the last menstrual period (LMP) method is an estimate. Only about 5% of women deliver on their exact due date. Most babies arrive between 38 and 42 weeks of pregnancy.
What if my menstrual cycles are irregular?
If your cycles are irregular, the LMP method may not be accurate. Ultrasound dating in the first trimester is more reliable for irregular cycles. You can also estimate based on the date of conception if known.
When will I feel the baby move?
First-time mothers typically feel fetal movement between 18 and 25 weeks. Women who have been pregnant before may feel movement earlier, around 15 to 20 weeks.
How is the due date calculated?
The most common method is Naegele's Rule, which adds 280 days (40 weeks) to the first day of your last menstrual period. Adjustments are made for shorter or longer menstrual cycles.
What are the signs of labor?
Signs include regular contractions, lower back pain, a "bloody show," water breaking, and pelvic pressure. Contact your healthcare provider if you experience these symptoms.
How can I track my pregnancy week by week?
Use our pregnancy calculator to track your baby's development week by week. You can also download pregnancy apps, keep a journal, or use a pregnancy tracker calendar.
Understanding Your Pregnancy Journey
Pregnancy is an incredible journey filled with remarkable changes for both you and your baby. Understanding the stages of pregnancy can help you prepare for what's to come and make informed decisions about your health and the health of your baby.
The Three Trimesters of Pregnancy
Pregnancy is divided into three trimesters, each lasting about 13 weeks. Each trimester brings unique developmental milestones for your baby and physical and emotional changes for you.
First Trimester (Weeks 1-12)
The first trimester is a time of rapid development for your baby. During this period, the fertilized egg implants in the uterus, and the embryo begins to form major organs such as the heart, brain, and lungs. Many women experience early pregnancy symptoms like fatigue, nausea, and breast tenderness during this trimester.
Second Trimester (Weeks 13-28)
The second trimester is often considered the "golden period" of pregnancy. Many women feel more energetic as morning sickness fades, and the baby's movements become noticeable. This trimester is marked by significant growth for the baby, who will develop facial features, fingerprints, and begin to hear sounds from the outside world.
Third Trimester (Weeks 29-40)
In the third trimester, your baby continues to grow and mature in preparation for birth. You may experience physical discomfort as your baby grows larger and takes up more space in your abdomen. Braxton Hicks contractions, also known as "practice contractions," may become more frequent as your body prepares for labor.
Key Milestones in Fetal Development
Your baby's development is a complex and fascinating process. Here are some key milestones:
- Week 4: The embryo implants in the uterine lining, and the placenta begins to form.
- Week 8: The embryo is now called a fetus. Limbs are visible, and the heart is fully formed.
- Week 12: The fetus can move its limbs, though you won't feel it yet. External sex organs begin to develop.
- Week 16: The fetus's hair begins to grow, and the mother may start to feel quickening (first movements).
- Week 20: Vernix caseosa, a waxy substance, covers the fetus's skin to protect it.
- Week 24: The fetus's lungs begin to produce surfactant, a substance necessary for breathing after birth.
- Week 28: The fetus can open and close its eyes and has a good chance of survival if born prematurely.
- Week 32: The fetus's bones are fully formed but still soft. The brain is developing rapidly.
- Week 36: The fetus's lungs are nearly mature, and it continues to gain weight.
- Week 40: The baby is considered full-term and can be born at any time.
Prenatal Care and Tests
Regular prenatal care is essential for monitoring your baby's development and ensuring a healthy pregnancy. Your healthcare provider will recommend various tests and screenings throughout your pregnancy, including:
- Ultrasounds: These imaging tests use sound waves to create pictures of your baby in the womb.
- Blood Tests: These check for conditions like anemia, diabetes, and infections.
- Genetic Screening: These tests assess the risk of certain genetic disorders in your baby.
- Glucose Screening: This test checks for gestational diabetes around 24-28 weeks.
- Group B Strep Test: This test checks for a common bacteria that can affect the baby during birth.
Preparing for Your Baby's Arrival
As your due date approaches, it's important to prepare for your baby's arrival. This includes:
- Creating a birth plan that outlines your preferences for labor and delivery
- Packing a hospital bag with essentials for you and your baby
- Setting up a nursery with a safe sleeping environment
- Taking childbirth education classes to learn about labor, delivery, and newborn care
- Arranging for help after the baby is born, such as meal preparation and childcare
Remember, every pregnancy is unique, and it's normal to have questions or concerns along the way. Your healthcare provider is your best resource for information and support throughout your pregnancy journey.