Gestational Age by Ultrasound Crown-Rump Length (CRL) & Due Date Calculator
Calculate exact gestational age (weeks and days) and Estimated Due Date (EDD) from first-trimester Crown-Rump Length (CRL in mm) according to the gold-standard Robinson and Hadlock fetal dating criteria.
Gestational Age (Weeks)
Calculator Inputs
Gestational Age (Weeks)
Additional Days (+Days)
Days Remaining to Expected Delivery
Total Gestational Days
Gestational Age Progress vs Remaining Days to 40 Weeks
First-trimester CRL (between 6 and 14 weeks) is clinically recognized by ACOG and ISUOG as the most accurate dating method (accuracy ±3-5 days).
This tool is a mathematical wellness and fitness estimation model for general educational guidance only. The results do not constitute medical diagnosis, clinical advice, or treatment plans. Always consult a qualified physician or certified dietitian before starting any dietary regimen, exercise program, or making health decisions.
Calculation Methodology
Robinson & Hadlock Standard Equation: Gestational Age in Days = 5.2876 * sqrt(CRL in mm) + 0.1584 * CRL + 33.917.
Frequently Asked Questions
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