Calculate your ideal weight and healthy weight range based on your height and gender. Uses multiple medical formulas to give you a comprehensive target weight range. Updated for 2026/27.
This calculator uses the BMI healthy weight range method. For your height, it calculates the weight range that gives a BMI between 18.5 and 24.9, which is considered healthy for most adults. The target weight shown is the midpoint of this range.
Robinson formula (1983): For men: 52kg + 1.9kg per inch over 5 feet. For women: 49kg + 1.7kg per inch over 5 feet.
Miller formula (1983): For men: 56.2kg + 1.41kg per inch over 5 feet. For women: 53.1kg + 1.36kg per inch over 5 feet.
Devine formula (1974): For men: 50kg + 2.3kg per inch over 5 feet. For women: 45.5kg + 2.3kg per inch over 5 feet.
Use this calculator as a general guide rather than an absolute target. Your ideal weight depends on factors including muscle mass, bone density, age, and overall health. A weight within the healthy BMI range combined with good fitness and nutrition is more important than hitting a specific number.
If you're significantly outside the healthy range, consider consulting a healthcare professional for personalized advice on achieving and maintaining a healthy weight.
Various ideal weight formulas were developed for different purposes and populations, explaining their discrepancies. The Devine formula (1974) was created for drug dosing calculations in medical settings, not aesthetic or health goals. Robinson and Miller formulas attempted to refine Devine for general population use. The Hamwi formula was designed for quick clinical estimates. Each uses different multipliers per inch of height and different base weights, reflecting different assumptions about ideal body proportions. These formulas were primarily developed using data from Western populations in the 1970s-1980s and don't account for modern understanding of body composition, ethnic variation, or individual differences in frame size and muscle mass. The BMI range method used in this calculator is more flexible, giving you a healthy weight range (typically 12-15kg spread) rather than a single target number, acknowledging that "ideal" weight varies between individuals of the same height. For a 175cm person, formulas might suggest anywhere from 63kg to 75kg as "ideal" — both could be perfectly healthy depending on the person's muscle mass and body composition. This range approach is more realistic than targeting a specific number. When these formulas were developed, obesity was less common and average fitness levels higher, so the weights they suggest often feel light by modern standards. Use them as general ballpark figures rather than precise targets.
Being slightly below the calculated ideal range doesn't automatically mean you're unhealthy, especially if you've always been naturally slim, have good energy, regular periods (for women), strong bones, and no history of eating disorders. Some people have naturally lower body fat set points and smaller frames making lower weights appropriate for them. However, being significantly underweight (BMI under 18.5) does increase risks: weakened immune system, osteoporosis, fertility problems, muscle wasting, and vitamin deficiencies. If you've lost weight unintentionally, feel constantly cold, experience hair loss or fatigue, or have irregular periods, these may signal genuine underweight issues requiring attention. Asian populations often have healthy weights in the lower portion of standard BMI ranges due to genetic differences in body composition. Very active endurance athletes like marathon runners frequently have BMIs of 18-20 which is healthy in their context given their fitness levels. That said, intentionally maintaining very low weight through restriction indicates potential eating disorder development regardless of current BMI. The key questions are: Is this weight natural for you without extreme dietary restriction? Do you have good energy, mental clarity and physical performance? Are your blood tests (iron, vitamin D, thyroid) normal? If yes to all, you may simply be naturally slim. If you're restricting intake, exercising excessively, or experiencing health problems, you need support regardless of whether you technically meet "underweight" criteria.
Obsessing over reaching a specific number on the scale often backfires by creating unhealthy relationships with food and exercise. Weight fluctuates 1-3kg daily due to water retention, sodium intake, menstrual cycle, digestive contents, and glycogen stores, so the number you see any given morning isn't particularly meaningful. Additionally, body composition matters far more than weight: someone at 70kg with 15% body fat looks completely different from someone at 70kg with 30% body fat. Focus instead on health markers and performance: How's your energy throughout the day? Can you climb stairs without breathlessness? Are your blood pressure, cholesterol and blood sugar healthy? Do you sleep well? How's your mood and mental health? Are you getting stronger or faster in workouts? Do your clothes fit comfortably? These indicators matter more than whether you weigh 68kg or 72kg. Set behavior-based goals instead of outcome-based ones: eat vegetables at every meal, strength train three times weekly, walk 10,000 steps daily, sleep 7-8 hours. Follow these behaviors and your body will settle at a healthy weight for you, which might not match a calculator's prediction but will be right for your individual physiology. Many people maintain excellent health at weights outside standard ranges, whilst others are unhealthy within them. A fit person at BMI 27 often has better health outcomes than an unfit person at BMI 22. The pursuit of a specific weight number can lead to yo-yo dieting, disordered eating, and worse health than simply maintaining a higher stable weight through consistent healthy habits. Your body may have a set point weight it naturally maintains when eating intuitively without restriction — fighting this through chronic dieting usually fails long-term and damages metabolic health.
Healthy BMI range (18.5-24.9) translates to weight range: 50.3kg to 67.8kg. Target midpoint: 59kg. This 17kg range acknowledges individual variation. A muscular woman might thrive at 67kg whilst a smaller-framed woman feels best at 52kg — both healthy.
Healthy BMI range gives weight range: 60kg to 81kg. Target midpoint: 70kg. A rugby player at 85kg with muscle mass might be healthier than a sedentary person at 70kg despite being above the range. Context and composition matter enormously.
Healthy weight range: 56.6kg to 76.3kg. Target: 66kg. Different formulas suggest: Devine = 72kg, Robinson = 69kg, Miller = 70kg, all within the healthy range but illustrating how formulas vary. Any weight in the 60-75kg range could be ideal depending on build and fitness.
Shift from weight-centric to health-centric goals by tracking meaningful health markers instead of just pounds. Get annual blood work checking cholesterol, blood sugar, vitamin D, iron and thyroid function. Monitor blood pressure aiming for 120/80 or below. Track fitness improvements: can you run further, lift heavier, hold a plank longer than last month? These functional gains indicate improving health regardless of weight changes. Measure waist circumference as abdominal fat predicts health risks better than total weight — men should aim below 94cm, women below 80cm. Take progress photos monthly as visual changes often precede scale changes when building muscle. Notice non-scale victories: better sleep, more energy, improved mood, clothes fitting differently, compliments on appearance, reduced medication needs. Pay attention to how you feel: do you have sustained energy, good digestion, regular menstrual cycles, stable mood? These subjective measures matter. Build muscle through strength training which may increase scale weight but decreases body fat percentage and improves metabolic health. Prioritize food quality and nutrient density over calorie counting: eating vegetables, protein, whole grains and healthy fats supports health even if it doesn't create rapid weight loss. Practice intuitive eating recognizing hunger and fullness cues rather than external rules. Accept genetic reality: not everyone can or should be thin, and health exists across a wide weight range. Many people maintain excellent health at higher weights, particularly if they're fit, eat well, manage stress, and sleep adequately. The pursuit of thinness often compromises actual health through chronic stress, sleep deprivation from early morning workouts, social isolation from diet restrictions, and metabolic damage from repeated dieting cycles. Better to be 10kg heavier living joyfully with good habits than achieving your "ideal weight" through miserable restriction that's impossible to maintain long-term.