For your height, a healthy weight is between 8st 13lb – 12st 1lb (57–77kg).
Required Height
5ft9in
175 cm
To have a BMI of 22 at 75kg, you would need to be this tall.
How this calculator works
This tool is designed to help you set realistic weight goals. By inputting your height and a target BMI (Body Mass Index), we calculate the exact weight required to hit that target. This is often more useful than guessing a number, as it aligns your goal with medical standards for healthy weight ranges.
Reverse BMI formula
The calculation is simple algebra derived from the standard BMI formula:
If you are 5ft 10in tall and want a BMI of 22:
1. Convert height to inches (70 inches).
2. Calculate: (22 × 70²) ÷ 703 = 153 lbs.
3. Convert to stone: 10st 13lb.
BMI categories and what they mean
Category
BMI Range
Underweight
< 18.5
Healthy Weight
18.5 – 24.9
Overweight
25 – 29.9
Obesity (Class 1)
30 – 34.9
Obesity (Class 2)
35 – 39.9
Severe Obesity
40+
*Note: If you are of South Asian, Chinese, Middle Eastern, Black African, or African-Caribbean origin, the BMI thresholds for overweight and obesity may be lower (usually 23 and 27.5 respectively) due to increased health risks at lower weights. Always check with a GP.
Limitations of BMI
BMI is a screening tool, not a diagnostic of body fatness or health. It has well-known limitations:
Athletes: Muscle weighs more than fat. A rugby player may have a high BMI but low body fat.
Pregnancy: BMI is not applicable during pregnancy.
Age: It may not be accurate for the elderly or those under 18.
Distribution: It does not account for where fat is stored (waist measurement is often a better health indicator).
Frequently Asked Questions
A Reverse BMI calculator works backwards from the standard Body Mass Index formula. Instead of just telling you your score, you enter your height and a 'Target BMI' to calculate exactly what you need to weigh (in kg, st, or lbs) to reach that goal.
According to the NHS, the healthy weight range for most adults is a BMI between 18.5 and 24.9. However, individual targets may vary based on muscle mass, age, and ethnic background.
Research indicates that people from South Asian, Chinese, Black African, and African-Caribbean backgrounds may have a higher risk of health conditions (such as type 2 diabetes) at a lower BMI. The NHS suggests lower thresholds (for example, 23 for overweight) for these groups.
The formula is: Weight = Target BMI × (Height in metres)². For example, if your target is 22 and you are 1.8m tall: 22 × (1.8 × 1.8) = 71.28kg.
Not always. BMI does not distinguish between fat, muscle, or bone mass. Athletes with high muscle mass may be classified as overweight despite having low body fat. Waist measurement is often a better tracking tool for athletes.
No. BMI for children and teenagers (under 18) must be calculated using age-and-sex specific growth charts (centiles). This tool is intended for adults only.
Many health professionals suggest aiming for the middle of the healthy range (around BMI 21–22) rather than the edges. Maintaining a stable weight within the healthy range is the primary goal.
While the standard categories apply to all adults, some research suggests that slightly higher BMI values may be protective for older adults (65+) against frailty. Consult a GP for personalised advice.
Sustainable progress matters. The NHS commonly recommends losing no more than 0.5kg to 1kg (about 1lb to 2lb) per week. Rapid dieting to hit a number is rarely sustainable long-term.
You can have a 'healthy' BMI but still carry excess visceral fat and have low muscle mass. In that case, improving body composition (strength training, adequate protein, and daily movement) may matter more than chasing a scale number.
References
For official medical advice, please consult the NHS BMI guidance.