Estimated Fetal Weight (EFW) Ultrasound Calculator (Hadlock Clinical Formula)
Calculate Estimated Fetal Weight (EFW in grams and ounces) from standard ultrasound biometry: Abdominal Circumference (AC), Femur Length (FL), and Biparietal Diameter (BPD) using the gold-standard Hadlock equation.
Estimated Fetal Weight (EFW in Grams)
Calculator Inputs
Estimated Fetal Weight (EFW in Grams)
Estimated Fetal Weight (kg)
Estimated Fetal Weight (lbs)
Estimated Fetal Weight Output
Ultrasound weight calculations have an inherent physiological margin of error of approximately ±10-15%. Clinical evaluation by an OB/GYN is essential.
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
Hadlock 3-Parameter Formula: Log10(EFW) = 1.335 - 0.0034 * (AC * FL) + 0.0316 * BPD + 0.0457 * AC + 0.1623 * FL. Fetal Weight in grams = 10^Log10(EFW).
Frequently Asked Questions
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