Target Weight for BMI Calculator
How much should you weigh to land at a given BMI (e.g. 22.0, the mid-point of WHO's normal range)? This tool inverts the BMI formula: W = BMI × (height/100)². Enter your height and target BMI to get the matching weight in kg and lb. Add your current weight and it also reports your current BMI plus how many kg / lb you need to gain or lose. It also surfaces the weights that correspond to the BMI 18.5, 22 and 25 reference points.
Enter a valid height and target BMI.
Target weight
63.6 kg
140.2 lb
Weight needed to reach that BMI
Current BMI
—
Enter your current weight to see how much to gain or lose.
Common BMI reference points
-
Normal — lower
— kg
BMI 18.5
-
Normal — mid
— kg
BMI 22.0
-
Overweight cut-off
— kg
BMI 25.0
BMI = weight(kg) / height(m)². WHO international: 18.5–24.9 normal; Asia-Pacific guideline: 18.5–22.9 normal, ≥ 25 obese. This tool is informational, not medical advice.
Formula
target weight (kg) = target BMI × (height_m)² where height_m = height_cm / 100 target weight (lb) = target weight (kg) / 0.45359237 current BMI = current weight (kg) / (height_m)² weight delta = target weight − current weight
- · WHO international BMI categories (adults): < 18.5 underweight, 18.5–24.9 normal, 25–29.9 overweight, ≥ 30 obese.
- · Asia-Pacific (WPRO and HK DH) cut-offs are tighter: < 18.5 underweight, 18.5–22.9 normal, 23–24.9 overweight, ≥ 25 obese — used widely across China, Japan, Korea, Singapore, HK and Taiwan.
- · BMI doesn't distinguish muscle from fat — athletes with high muscle mass may have BMI > 25 without excess body fat. Read it alongside body-fat %, waist circumference and waist-to-hip ratio.
- · A target BMI around 22 sits near the all-cause-mortality nadir in large pooled cohorts (Berrington de Gonzalez et al., NEJM 2010); 21–23 is commonly suggested for Asian populations.
- · Not suitable for children under 18 — use the WHO Growth Standards (age- and sex-specific z-scores) instead.
- · BMI is also distorted in pregnancy / lactation, older adults (> 65), severe edema and amputees.
- · References: (1) WHO, "Body mass index — BMI"; (2) WHO WPRO 2000 Asia-Pacific cut-offs; (3) Berrington de Gonzalez A. et al., NEJM 363:2211 (2010); (4) HK Department of Health "Obesity in Adults" guideline.
Frequently asked
Should I target a BMI of 22 or 25?
BMI 22 sits closer to the all-cause-mortality nadir in large pooled cohorts (Berrington de Gonzalez et al., NEJM 2010; Global BMI Mortality Collaboration, Lancet 2016) and is the midpoint of the WHO Asia-Pacific normal range. BMI 25 is already the obese cut-off under Asia-Pacific guidelines (overweight under the international cut-off) — not a healthy target. In practice: (1) If you are already in the normal range, target 21–23. (2) If you are underweight (BMI < 18.5), aim to gain into 19–22. (3) For severe obesity (BMI > 35), losing 5–10 % of body weight is clinically valuable — you do not need to land at 22 in one go. (4) For older adults (> 65), studies suggest BMI 23–27 has the lowest mortality, so do not chase 22 dogmatically.
I lift weights regularly; my BMI is 26 but my body fat is only 12 %. What's going on?
The BMI formula only uses height and weight; it can't distinguish muscle from fat. **One kg of muscle has about 70 % the volume of one kg of fat, but they weigh the same on a scale.** Resistance-trained athletes carry extra muscle, so their weight reads as "overweight" while body fat is low — this is a false-positive overweight by BMI. **What to do instead**: (1) Use body-fat percent — healthy men 10–20 %, women 18–28 %; (2) Add waist circumference — healthy under WHO Asia-Pacific is < 90 cm (M) / < 80 cm (F); (3) DEXA or BodPod give the most accurate body composition but cost more; home bioimpedance scales drift ±3–5 % with hydration. **Bottom line**: BMI underestimates leanness in athletes — your BMI 26 doesn't mean you need to lose weight. (A sedentary person with BMI 26 is a different story.)
What is the safest rate to go from my current weight to my target weight?
**Losing weight**: the medical consensus is **0.5–1.0 kg per week (2–4 kg per month)**, which requires about a 500–1000 kcal/day deficit. Faster than 2 kg/week causes: (1) accelerated muscle loss (up to 1/3 of the weight loss can be lean tissue); (2) higher gallstone risk; (3) larger-than-expected metabolic adaptation; (4) higher rebound rate (yo-yo effect). Sources: CDC, NICE, AACE/ACE clinical guidelines. **Gaining weight**: healthy gain is 0.25–0.5 kg/week; faster gains are stored mostly as fat. Pairing the surplus with resistance training routes more of the gain into lean muscle. **Example**: a 170 cm, 75 kg man (BMI 28) targeting BMI 22 (≈ 63.6 kg) needs to lose 11.4 kg. At 0.7 kg/week that is 16 weeks (4 months). Most people drop faster initially (water weight) then stabilise near 0.5 kg/week — be patient.
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