Aim: The aim of the study is to use the formula demonstrated by Chi-Feng Su to determine the estimated birth weight (EBW) at 20–24 weeks gestation and try to find out the correlation between the estimated fetal weight with the actual birth weight in our local population. Materials and methods: It is a retrospective study done at the Department of Obstetrics and Gynecology, RajaRajeswari Medical College, Bengaluru. Fifty patients who were booked, followed up, and delivered at our institution were selected for our study after meeting inclusion and exclusion criteria. Participant's demographic characters like age, gravida, weight, body mass index (BMI), last menstrual period (LMP), and others were noted down as per the protocol. Their mid-pregnancy BMI, and fetal biometry report at 20–24 weeks were noted. Using the study formula, their anticipated fetal weight was calculated. After delivery, the exact birth weight was noted and was correlated with the predicted weight. Results: In the study, majority (66%) aged less than 25 years and only 3 patients were aged above 30 years; 50% of the cases were second gravida; 60% of the participants had BMI between 20 and 25, 16% has BMI above 25, and 24% has BMI less than 20. The best correlation was seen in the weight group between 2.6 and 3.5 kg. Conclusion: The formula demonstrated by Chi-Feng Su had variance as high as 0.303. Our study also showed high variability when the error was +17.6% with birth weight >2.5 kg.