Enter your height and weight to instantly calculate your Body Mass Index, find your healthy weight range, and understand your BMI category. Supports metric and imperial units — free, no signup required.
Body Mass Index (BMI) is a value derived from height and weight. Enter your details to visualize your results.
* These ranges apply to adults aged 18 and above. BMI interpretation differs for children and teens.
Most people know they should check their BMI regularly — but going to a clinic just to check a number takes time, money, and effort. That's why we built this. Open the page, enter your height and weight, and get your BMI result instantly — no appointment, no clinic visit needed. Use it weekly, monthly, or whenever you feel like checking. It takes less than 10 seconds and gives you a clear idea of where you stand — so when you do visit a doctor, you already know what to expect.
Body Mass Index is calculated the same way for both men and women. The result is compared against standard weight categories to determine whether a person is underweight, in the normal weight range, overweight, or obese.
Enter your height and weight, pick metric or imperial — and your BMI result appears instantly. No signup, no app, everything runs in your browser.
Metric formula
BMI = Weight (kg) ÷ Height (m²)
Imperial / US formula
BMI = (Weight (lbs) ÷ Height (in²)) × 703
Both formulas give the same result — pick whichever unit system you're comfortable with. Your BMI and category show up immediately, no account needed.
Once you receive your BMI number, here is how to interpret it using the standard WHO adult classification for people aged 20 and older:
A BMI under 18.5 suggests body weight may be too low relative to height. This can sometimes be associated with nutritional deficiencies, a weakened immune system, or reduced bone density. If you consistently fall in this range, a conversation with a healthcare provider is worthwhile.
This is the healthy weight range associated with the lowest risk of weight-related health conditions for most adults. People in this category face a statistically lower risk of type 2 diabetes, hypertension, and cardiovascular disease compared to those in other categories.
A BMI in this range suggests carrying more body weight than is considered optimal for your height. Lifestyle changes including a more balanced diet and increased physical activity can often bring BMI back into the normal weight range over time.
A BMI of 30 or higher is classified as obese, further divided into Class I (30–34.9), Class II (35–39.9), and Class III (40 and above). Higher values in this range are associated with increased risk of serious conditions including heart disease, stroke, sleep apnea, type 2 diabetes, and certain cancers.
A BMI between 18.5 and 24.9 maps to a different body weight depending on how tall you are. For an adult standing 5 feet 7 inches (170 cm), the weight that falls within a normal BMI sits roughly between 118 and 159 pounds (54 to 72 kg). For someone at 5 feet 10 inches (178 cm), that same BMI range corresponds to approximately 129 to 174 pounds (59 to 79 kg).
These figures are useful reference points, but they are not a precise target. BMI is a screening measure that does not account for individual differences in muscle mass, bone density, or body composition. Use this range as a starting guide, not a strict personal goal.
The BMI formula is identical for men and women, but body composition naturally differs between them. Women typically carry a higher proportion of body fat than men at the same BMI value — meaning a woman and a man with the same number may have quite different body fat percentages. This does not change the standard BMI categories, but it is useful context when interpreting your result.
For older adults — muscle decreases and fat increases with age even if weight stays the same. Some research suggests adults over 65 may benefit from a slightly higher BMI — but always discuss this with your doctor.
BMI is a useful screening tool, but it is not a perfect measure of health or body composition. Here are the key things it does not account for:
Muscle mass vs. fat mass
BMI only looks at total weight in relation to height. A professional athlete with dense muscle may have a high BMI but very low body fat. Conversely, someone with a normal BMI may carry a high proportion of body fat with little muscle — sometimes called normal weight obesity.
Fat distribution and visceral fat
Where fat is stored matters as much as how much is present. Visceral fat stored around the abdominal organs carries significantly higher health risks than fat stored in the hips and thighs. BMI cannot measure fat distribution or identify where excess weight is being carried.
Age and sex differences
As people age, body composition naturally shifts toward less muscle and more fat even at the same body weight. Women also tend to carry more body fat than men at the same BMI. These variations are not captured in the standard BMI classification.
Ethnicity
Research shows that weight-related health risks can appear at lower BMI values in certain ethnic groups, particularly those of South Asian descent. Several health authorities publish adjusted BMI thresholds for these populations, recognising that standard cut-off points may not accurately reflect risk for all groups.
Children and teenagers
Standard adult BMI ranges do not apply to those under 18. For young people, BMI must be assessed against age- and sex-specific growth charts. The raw number alone carries no meaning without that age-adjusted context.
Use this calculator as a starting point, not a final verdict. For a thorough understanding of your health, combine BMI with other assessments such as waist circumference, body fat percentage, blood pressure, cholesterol levels, and a conversation with your doctor.
BMI is the most widely used screening metric because it needs only two inputs and no specialist equipment. However, other tools can provide information that BMI alone cannot capture.
Waist circumference
A direct measure of abdominal fat. A waist measurement above 88 cm (35 inches) for women or 102 cm (40 inches) for men is generally considered a risk indicator for metabolic conditions, regardless of BMI category.
Body fat percentage
Measures what proportion of total body weight comes from fat tissue. More informative than BMI for people with high muscle mass such as athletes, or those who have lost muscle with age.
Waist-to-hip ratio
Compares waist and hip measurements to assess how fat is distributed across the body. A higher ratio indicates more abdominal fat, which carries greater cardiovascular and metabolic risk than fat stored elsewhere.
Getting your BMI into a healthy range — and keeping it there — is less about willpower and more about building habits that feel sustainable month after month. No crash diets, no six-days-a-week gym schedules. Just practical shifts that compound quietly over time.
Eat the right foods daily
Stick to your daily routine meals — roti, dal, sabzi, fruits — whatever you normally eat at home. These are already balanced for your body. Add fruits wherever you can fit them in. The simpler and more routine your eating is, the easier it is to maintain a healthy weight.
Exercise daily
Daily exercise is just as important as what you eat. Even 30 minutes of walking, cycling, or any physical activity you enjoy — done consistently every day — makes a bigger difference than any diet plan. The key word is daily — not occasionally.
Walking and running are enough
Walking and running are the best free exercises for maintaining a healthy weight — no cost, no equipment, no gym membership needed. If you can afford a gym, that works too. But honestly, a daily walk or run is enough. Consistent free exercise beats an expensive gym routine you stop after a month.
Get at least 8 hours of sleep
Less sleep affects your hormones — and when hormones are off, you feel hungrier than you actually are. This leads to eating more and gaining weight without realizing why. Make sure you get at least 8 hours of sleep every night. It's one of the easiest things you can do for weight management that most people ignore.
Managing stress helps control weight
There is a direct connection between stress and weight gain. When you are stressed, your body releases a hormone called cortisol. This hormone increases hunger and causes your body to store fat — especially around the stomach area. Managing stress is not just good for your mind, it directly affects your weight too. Simple daily habits like walking, talking to someone, or taking breaks can help keep stress levels in check.
Reduce sugary drinks
Cold drinks, juices, and chai all have one thing in common — high sugar content. Chai also has milk which adds extra calories. These drinks feel small but add up significantly over the day. Switching to plain water or plain tea without sugar is one of the simplest changes you can make to manage your weight without changing your food at all.
Eat properly — not less
Eating less is not the answer — if you eat too little, your body loses energy and you can face many other health problems even if your weight goes down. The right approach is eating properly — balanced meals at the right time, not skipping meals, and not overeating either. A body that gets the right nutrition manages weight naturally over time.
One number. Two inputs. Ten seconds. That's all it takes to know where you stand. No clinic visit, no equipment, no waiting. Check it today, check it next month — and track how your body changes over time. Small consistent checks beat one annual visit every time.
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A BMI Calculator estimates your Body Mass Index from your height and weight — and tells you whether you're underweight, normal weight, overweight, or obese. Enter your details and get the result instantly, no clinic visit needed.
Enter your weight and height — metric (kg/cm) or imperial (lbs/inches) — and the calculator does the rest. The formula is weight ÷ height² but you don't need to do any math manually. Result appears in seconds.
BMI gives a useful general estimate — but it doesn't account for muscle mass, body fat percentage, or body composition. A person with high muscle mass may show as overweight even if they're healthy. Use it as a starting point, not a final diagnosis.
For most adults, a BMI between 18.5 and 24.9 is considered normal weight. Below 18.5 is underweight, 25-29.9 is overweight, and 30 or above is obese — based on WHO standard classifications.
Not exactly — research shows South Asians can have higher health risks at lower BMI values compared to Western populations. Some health authorities recommend a lower overweight threshold of 23 instead of 25 for South Asian adults. Always discuss with your doctor for personalized advice.
It depends on height. A person weighing 70 kg and 1.75 m tall has a BMI of 22.9 — normal weight. The same 70 kg at 1.60 m gives a BMI of 27.3 — overweight. Height matters as much as weight.
The formula stays the same for all adults — but as you age, muscle mass decreases and body fat increases, so your BMI may shift even if your weight stays the same. Checking regularly helps you track these changes over time.
No — this tool is for adults aged 18 and above only. BMI for children works differently because healthy ranges change with age and development stage. For children, age-adjusted growth charts are needed.
Any adult who wants to know their BMI quickly and privately — no signup, no clinic visit needed. Whether you're starting a fitness goal, checking in monthly, or just want to know your number before a doctor's appointment.
Yes — many people check their BMI weekly or monthly alongside how they feel, energy levels, and fitness performance. BMI alone doesn't tell everything, but tracking it regularly gives you a clear picture of how your body is changing.
Written by AtraKit Team
This calculator follows WHO standard BMI classifications. Always consult a doctor for medical advice.
Last Updated: June 2026
* While this tool can point you in a useful direction, it is not a clinical assessment. If your result concerns you, or if you have an existing health condition, the right next step is a conversation with a qualified medical professional.