Pregnancy Due Date & Age by Ultrasound Calculator (USG)
Clinical obstetric calculator for pregnancy ultrasound dating. Uses Crown-Rump Length (CRL in 1st trimester) or ultrasound scan gestational age to determine exact delivery due date (EDD).
Input Parameters
Instant Calculation Result
Adjust values on the left to calculate live results.
In-Depth Guide & Mathematical Methodology
🩺 ACOG Ultrasound Dating Accuracy
1st Trimester (CRL ≤ 14 weeks): Most accurate clinical dating method (±5 to 7 days). If USG differs from LMP by > 5 days, the ultrasound due date replaces the LMP due date.
2nd Trimester (14-22 weeks): Accuracy within ±7 to 10 days (BPD, HC, AC, FL biometry).
3rd Trimester (22+ weeks): Accuracy within ±21 days due to natural fetal growth variations.
Frequently Asked Questions (FAQ)
What is the Pregnancy Due Date & Age by Ultrasound Calculator (USG) and how does it work?
Clinical obstetric calculator for pregnancy ultrasound dating. Uses Crown-Rump Length (CRL in 1st trimester) or ultrasound scan gestational age to determine exact delivery due date (EDD).
How do I use this Pregnancy Due Date & Age by Ultrasound Calculator (USG)?
Select ultrasound method (Ultrasound Gestational Age or Crown-Rump Length CRL). Select the date the ultrasound scan was performed. Enter the gestational weeks and days stated on the sonogram report. View exact current gestational age today, ultrasound due date (EDD), and remaining days countdown.
What mathematical formula is used in this calculation?
ACOG Ultrasound Dating Guidelines: 1st Trimester CRL ultrasound is the gold standard for gestational age assignment (±5-7 days error margin). EDD = Scan Date + (280 - (ScanWeeks × 7 + ScanDays)).
Is the Pregnancy Due Date & Age by Ultrasound Calculator (USG) on FindCalculator free to use?
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