For educational and reference use only. These calculators do not replace clinical judgement, local protocols, or a qualified clinician. Verify every result independently before it informs patient care.
Women's & obstetric imaging
Estimated Fetal Weight (Hadlock)
Estimated fetal weight from four biometric measurements using the Hadlock 1985 four-parameter equation (BPD, HC, AC, FL). Enter measurements in mm.
Result
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Enter all values to calculate.
Formula
log₁₀(EFW) = 1.3596 − 0.00386·AC·FL + 0.0064·HC + 0.00061·BPD·AC + 0.0424·AC + 0.174·FL (all in cm; EFW in grams).
Disclaimer
EFW carries an inherent error of roughly ±15%. Assess against a gestational- age growth percentile (e.g. Hadlock or INTERGROWTH-21st) before diagnosing growth abnormality.
For educational and reference use only. These calculators do not replace clinical judgement, local protocols, or a qualified clinician. Verify every result independently before it informs patient care.
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