The ideal body mass index (BMI) range for adults is between 18.5 and 24.9. This range is considered to reflect a healthy weight relative to height, associated with a lower risk of developing various health conditions. A BMI below 18.5 is classified as underweight, while a BMI of 25 or above indicates being overweight or obese. Regular monitoring of BMI can help individuals assess their health status and make related lifestyle changes as needed. However, while BMI is a useful screening tool, it does not consider factors such as muscle mass or body composition, so additional assessments may be necessary for a complete evaluation.