Our advanced Pregnancy Calculator helps you determine your estimated due date, track your pregnancy progress week-by-week, and understand your baby’s development milestones. Based on your last menstrual period (LMP), our calculator provides accurate results that align with medical standards used by healthcare professionals.
Current Milestone: –
Enter your information to see your baby’s current development stage.
How to Use the Pregnancy Calculator
Get accurate pregnancy information in three simple steps:
Enter the first day of your last menstrual period. This is the date most healthcare providers use to calculate your due date.
Our calculator will instantly determine your estimated due date and current pregnancy status.
Monitor your pregnancy week-by-week with detailed milestone information and a visual progress bar.
Why Track Your Pregnancy Progress?
Accurate Planning
Prepare for your baby’s arrival with an accurate due date to plan maternity leave, baby showers, and medical appointments.
Milestone Tracking
Understand your baby’s development at each stage and know what to expect during each trimester.
Healthcare Coordination
Share accurate pregnancy information with your healthcare provider for better prenatal care.
Understanding Your Pregnancy Timeline
Once you get your results from the pregnancy calculator, you’ll see several key dates and terms. Here’s a quick guide to what they mean, helping you better understand your journey.
Gestational Age vs. Fetal Age
Our calculator determines the gestational age of your pregnancy, which is the standard used by doctors. It’s counted from the first day of your last menstrual period (LMP). This means that during the first two weeks of your “pregnancy,” you weren’t actually pregnant yet—your body was preparing for ovulation. Fetal age, on the other hand, is the actual age of the growing baby, counting from the date of conception. It is typically two weeks behind the gestational age.
The Science: Naegele’s Rule
The calculation method is based on Naegele’s Rule. This simple formula estimates the due date by adding one year, subtracting three months, and adding seven days to the first day of your LMP. Our calculator automates this by simply adding 280 days (40 weeks) to your LMP, which yields the same result and is the universally accepted method for predicting a due date for a regular 28-day cycle.
A Guide to the Three Trimesters
Pregnancy is a 40-week journey divided into three distinct stages, or trimesters. Each one brings unique changes and developmental milestones for both you and your baby. Our pregnancy tracker will help you follow along week-by-week.
First Trimester (Weeks 1-13)
This is a period of rapid and fundamental development. Although you may not look pregnant on the outside, your body is working incredibly hard. Key events include:
- For Baby: The neural tube (which becomes the brain and spinal cord) forms, the heart begins to beat, and all major organs and body parts start to develop. By the end of this trimester, your baby is fully formed, complete with tiny fingers and toes.
- For Mom: You may experience classic early pregnancy symptoms like morning sickness, fatigue, and breast tenderness. Hormonal changes are in full swing, impacting your mood and energy levels.
Second Trimester (Weeks 14-27)
Often called the “honeymoon” phase of pregnancy, many women feel their best during these weeks. Morning sickness often subsides, and energy levels may increase. This is a great time to focus on preparation and enjoy the journey.
- For Baby: The baby’s movements (quickening) can be felt for the first time. The baby can now hear and swallow, and their unique fingerprints and footprints have formed. Gender can often be determined via an anatomy scan ultrasound around week 20.
- For Mom: Your baby bump will become more noticeable. You may feel more energetic and can enjoy this time to plan, prepare the nursery, and attend prenatal classes.
Third Trimester (Weeks 28-40+)
This is the final stretch as you and your baby prepare for delivery. The baby grows rapidly, gaining weight and maturing its lungs for life outside the womb. Rest becomes increasingly important.
- For Baby: The baby’s bones are fully developed, and they begin to practice breathing movements. They will typically turn into a head-down position in preparation for birth. Their brain is developing rapidly.
- For Mom: You may feel more physical discomfort due to the baby’s size, such as backaches, shortness of breath, and difficulty sleeping. Braxton Hicks contractions (practice contractions) may also begin as your body prepares for labor.
Pregnancy Calculator FAQs
Our calculator uses the standard method of adding 280 days (40 weeks) to the first day of your last menstrual period (LMP). It’s highly accurate for those with regular cycles, but remember that only about 5% of babies arrive on their exact due date. It’s a trusted estimate used by doctors worldwide.
If your LMP date is unknown, the most accurate way to determine your due date is through a dating ultrasound, which your healthcare provider can perform. If you know your conception date, you can add 266 days to get a close estimate.
While conception typically happens about two weeks after your period starts, the first day of the LMP is a more certain and easily identifiable date. This standardized method, known as calculating gestational age, ensures consistency among all healthcare providers.
Pregnancy is divided into three trimesters: First (weeks 1-13), Second (weeks 14-27), and Third (week 28 to birth). Each has distinct developmental milestones. Our calculator automatically determines which trimester you are in.
For IVF, dating is more precise. You should use your embryo transfer date, not your LMP. For a 3-day embryo transfer, add 263 days. For a 5-day embryo transfer, add 261 days. Always confirm with your fertility specialist.
Congratulations! Your first step should be to schedule an appointment with a healthcare provider (OB-GYN or midwife) to confirm the pregnancy and start prenatal care. They will guide you on nutrition, prenatal vitamins, and the next steps for a healthy pregnancy.
Yes, it’s possible. The initial due date from your LMP is an estimate. Your doctor may adjust your due date after a first-trimester ultrasound, which measures the baby’s size and can provide a more accurate age. This is especially common if your cycles are irregular.
The anatomy scan is a detailed ultrasound typically performed between weeks 18 and 22 of pregnancy. A sonographer will check the baby’s major organs, limbs, and overall physical development. It’s also when you can often find out the baby’s sex if you choose to.
If you are “10 weeks and 4 days” pregnant, you are in your 11th week. Just like when a baby is 6 months old, they are in their first year of life. So, when our calculator shows you are 10 weeks pregnant, it means you have completed 10 full weeks and are now living in your 11th.
Yes, very normal. Many first-time mothers go past their estimated due date. A pregnancy is considered ‘post-term’ if it extends beyond 42 weeks. Your healthcare provider will monitor you and your baby closely and may discuss inducing labor if necessary.