Estimate your due date from your first trimester ultrasound (CRL).
- Date of Ultrasound
- Crown-Rump Length (CRL)
The calculator will then estimate your due date and the gestational age at the time of the scan.
Why CRL Matters
CRL is the most accurate single ultrasound measurement for dating a pregnancy in the first trimester, especially between about 7 and 13 weeks. Later in pregnancy, clinicians use other measurements such as head size or femur length to assess growth, but those are not the inputs used by this calculator.
Important Medical Notes
This calculator is an educational tool to help you understand the data on your ultrasound report. The official due date used for your medical care is the one determined by your sonographer and confirmed by your doctor. Always use the EDD in your official medical records for scheduling and planning purposes.