The average weight of a 13-year-old girl typically ranges between about 34.5 kg to 67.1 kg, with the 50th percentile (average) being around 45.8 kg. The weight can vary widely due to factors such as height, puberty stage, genetics, and body composition. According to percentile data, some common weights for 13-year-old girls are:

• 5th percentile: About 34.5 kg
• 10th percentile: About 36.3 kg
• 25th percentile: About 40.4 kg
• 50th percentile (average): About 45.8 kg
• 75th percentile: About 52.6 kg
• 90th percentile: About 61.2 kg
• 95th percentile: About 67.1 kg

This means a healthy weight for a 13-year-old girl can fall anywhere within this range, depending on individual growth and development.