Pregnancy Calculator

Find out how many weeks pregnant you are and your trimester.

Pregnancy dates are estimates and do not replace prenatal medical care.

Pregnancy week estimateDue date and trimesterReviewed for accuracy

Pregnancy calculator

Choose a calculation method and enter the date details you know.

Calculation method

LMP method counts pregnancy from the first day of the last period.

days

Cycle length can shift estimated ovulation and due date.

Pregnancy dating is approximate.
Ultrasound or clinician assessment may revise dates.
Prenatal care should be guided by healthcare professionals.

Estimated pregnancy week

12w 0d

Approximately 84 days gestational age.

Estimated due date

Wednesday, December 30, 2026

Based on last menstrual period.

Current trimester

First trimester

Days until due date

196 days

Pregnancy progress

30.0%

Pregnancy dates are estimates. Prenatal care, ultrasound dating, IVF details, and complex medical histories should be guided by qualified healthcare professionals.

Personalized interpretation

Based on last menstrual period, you may be approximately 12 weeks and 0 days pregnant.

Your estimated due date is Wednesday, December 30, 2026.

You may currently be in the first trimester.

Pregnancy dating is approximate and may be revised after an ultrasound or clinician assessment.

Seek medical care promptly for concerning symptoms such as heavy bleeding, severe pain, fainting, chest pain, shortness of breath, severe headache, or reduced fetal movement later in pregnancy.

Pregnancy timeline overview

Pregnancy start / LMP

Mar 25, 2026

Estimated conception

Apr 8, 2026

Current week

Jun 17, 2026

Third trimester starts

Oct 7, 2026

Estimated due date

Dec 30, 2026

This timeline is based on the selected calculation method. Actual clinical dates may vary.

Gestational age explained

Gestational age means how far along a pregnancy is.
It is usually counted from the first day of the last menstrual period.
Gestational age is often about two weeks more than time since conception.
Clinicians may use ultrasound and medical history to confirm or adjust dates.

Due date and trimester guide

First trimester

Weeks 1–13

Early pregnancy dating is commonly based on gestational age from LMP.

Second trimester

Weeks 14–27

Prenatal care timing and scans should follow clinician guidance.

Third trimester

Weeks 28–40+

The final trimester includes continued growth, monitoring, and birth preparation.

Due date is an estimated delivery date, not a guaranteed birth date. Most babies are not born exactly on the due date, and trimester boundaries can vary slightly by source.

Calculation methods explained

Last menstrual period

Uses the first day of your last period and cycle length.

Conception date

Uses a known or estimated conception date.

Due date

Works backward from an existing estimated due date.

IVF transfer

Uses transfer date and embryo age.

Why dates can change

Exact delivery date cannot be predicted by a calculator. Calculated pregnancy week is a planning estimate, not a diagnosis.

Irregular cycles
Uncertain LMP date
Ovulation timing
Early ultrasound measurements
IVF details
Clinician assessment
Medical history

Limitations and medical disclaimer

Calculator results are informational only. Pregnancy dating is approximate, and prenatal care should be guided by healthcare professionals.

IVF details and complex medical histories should be reviewed clinically.

Seek urgent medical attention for symptoms such as heavy bleeding, severe abdominal pain, fainting, severe headache, chest pain, shortness of breath, or reduced fetal movement later in pregnancy.

Formula / date explanation

LMP method: Estimated Due Date = First Day of Last Menstrual Period + 280 days
Conception method: Estimated Due Date = Conception Date + 266 days
Gestational Age = Today − First Day of Last Menstrual Period
Pregnancy Progress = Gestational Age Days ÷ 280 × 100

280 days is about 40 weeks from LMP. 266 days is about 38 weeks from conception. IVF due date depends on transfer date and embryo age. Ultrasound or clinician assessment may override calculator estimates.

Frequently Asked Questions