Overweight BMI: What Range Is Classed as Overweight? 

• Give the range straight away, then the weight corresponds to seven common heights so you can check yourself in stones or kilograms.
• Shows both formulas with worked examples, including the imperial one most people get wrong.
• Explains why the overweight band is the exact range where BMI is least reliable, and what to check alongside it.
• Sets out what the number does and does not mean, including the point at which it starts to matter clinically.

For most adults in the UK, a body mass index (BMI) of 25 to 29.9 is classed as overweight. Below 25 is the healthy weight range, and 30 or above is classed as obesity.

Different thresholds apply to some groups. For people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family backgrounds, the overweight range is a BMI of 23 to 27.4, because health risk appears at a lower BMI in these groups.

If you have just worked out your number and landed in this range, the useful thing to know is this: the overweight band is the exact part of the BMI scale where the number on its own tells you the least. This page explains why, what to check alongside it, and what the range actually means.

Key things to know

• A BMI of 25 to 29.9 is classed as overweight for most UK adults. Healthy weight is 18.5 to 24.9, and obesity begins at 30.
• For several family backgrounds the overweight range is 23 to 27.4, with obesity beginning at 27.5.
• Overweight is a classification band, not a diagnosis or a disease. It describes a statistical level of risk, not a condition you have.
• BMI does not measure body fat, and it cannot tell muscle from fat or say where fat is stored.
• BMI has limitations at every level, particularly when someone has a high muscle mass or carries a large amount of abdominal fat.
• Waist to height ratio adds the information BMI misses. Keeping your waist to less than half your height is the target used in UK guidance.
• A BMI of 27 can be relevant to weight-management treatment in some circumstances, but eligibility depends on the specific medicine, your health conditions and an individual clinical assessment.

What body mass index (BMI) range is classed as overweight?

A BMI of 25 to 29.9 is the overweight range for most adults in the UK. It sits between the healthy weight range and the obesity range.

What are the full BMI categories?

These boundaries are not biological cliff edges. Risk rises gradually across the whole scale, and nothing changes about your body between a BMI of 24.9 and 25.0. Each band is a bmi category used for consistency, not a switch at 25, and the table works much like a standard bmi chart.

What weight is overweight at my height?

Because BMI depends on height, the same weight can land in different categories for different people. This table shows the weight range that corresponds to a BMI of 25 to 29.9 at seven common heights.

You can use this table much like a BMI chart for a quick height-based check.

Below the lower figure for your height, BMI falls in the healthy weight range. Above the upper figure, it reaches the obesity range.

How do you work out your BMI?

BMI is your weight divided by your height squared. There are two versions of the sum depending on which units you use, and the imperial one has an extra step that people frequently miss.

The metric formula

To calculate BMI in metric units, divide your weight in kilograms by your height in metres, then divide by your height in metres again.

Working example: someone weighing 82 kg who is 1.75 m tall. 82 divided by 1.75 is 46.86. Divide that by 1.75 again and you get 26.8. That is in the overweight range. The same method applies to adult men and women, but not to children.

The imperial formula

Divide your weight in pounds by your height in inches, divide by your height in inches again, then multiply by 703.

That final multiplication is the step people forget, and leaving it out produces a number so small it looks like an error. Convert stones to pounds first by multiplying by 14, and convert feet to inches by multiplying by 12 and adding the remainder.

Worked example: someone weighing 12 stone 8 pounds who is 5 feet 8 inches tall. That is 176 pounds and 68 inches. 176 divided by 68 is 2.588. Divide by 68 again and you get 0.03806. Multiply by 703 and you get 26.8. The same answer as the metric example, because it is the same person. If you do not want to work it out manually, you can use a bmi calculator, but the result still needs interpretation.

Getting an accurate measurement

• Weigh yourself at the same time of day, ideally in the morning before eating.
• Measure your height without shoes, standing straight with your heels against a wall.
• Do not rely on the height on your driving licence or on a number you remember from your twenties. Height reduces slightly with age.
• Small errors matter more than people expect. Being wrong about your height by two centimetres can shift your BMI by roughly half a point.

Why are the thresholds lower for some people?

Because cardiometabolic risk, meaning the risk of conditions such as type 2 diabetes and heart disease, appears at a lower BMI in some populations.

UK guidance sets lower thresholds for people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family backgrounds. For these groups, overweight is a BMI of 23 to 27.4, and obesity begins at 27.5.

The reason is that these groups tend towards more central adiposity, meaning a greater proportion of fat carried around the abdomen and organs at any given BMI. Abdominal fat carries more health risk than fat stored elsewhere, so the same BMI reflects a different level of risk.

This is not a different or stricter standard. It is the same level of risk arriving at a different number. Someone with a BMI of 25 from one of these backgrounds may carry a similar level of risk to someone with a BMI of 27 from another.

What does an overweight BMI actually mean?

It means your weight relative to your height falls in a band associated with a modestly increased likelihood of certain health conditions across a population. It is not a diagnosis, and it is not a disease.

That distinction matters. An overweight BMI is a classification rather than a diagnosis. What matters clinically is the wider picture, including waist size, blood pressure, blood sugar, cholesterol and any weight-related symptoms or conditions.

Two people can both have a BMI of 27 and be in completely different situations. One may have a large waist, a raised blood pressure and a family history of type 2 diabetes. The other may have a small waist, normal blood tests and be physically active. The number is identical. The clinical picture is not.

Is being overweight associated with health risks?

Not necessarily, and this is one of the few honest answers on the subject. As BMI rises further into obesity, the higher risk extends to several health conditions and more serious long-term outcomes, and obesity can lower life expectancy by 2 to 10 years. Across a population, higher BMI is associated with higher rates of several conditions.

BMI is only one part of the picture. Health risk is influenced by factors such as waist size, blood pressure, blood sugar, cholesterol, physical activity, age and existing medical conditions. A BMI in the overweight range does not by itself tell you whether someone is healthy or unhealthy.

Why BMI does not tell the whole story

BMI becomes less useful when used on its own because it cannot distinguish between muscle and fat or show where body fat is stored. Someone with a high muscle mass may have a higher BMI without having excess body fat, while someone with a less muscular build may have a lower BMI but still carry a substantial amount of abdominal fat.

What does BMI not account for?

• Muscle mass. Muscle is denser than fat, so BMI does not tell the whole story about health risk or total body fat. UK guidance says BMI should be interpreted with caution in adults with high muscle mass, because it may be a less accurate measure in this group.
• Fat distribution. BMI says nothing about whether fat is carried around the abdomen or on the hips and thighs, and that difference matters more than the total; waist size can be a useful complementary measure.
• Age. BMI should be interpreted with caution in people aged 65 and over, taking into account other conditions and the possible protective effect of a slightly higher BMI in later life.
• Family background. Covered above. The standard thresholds do not fit everyone.
• Body frame and proportions. Two people of the same height with different builds can carry different amounts of lean tissue.
• Pregnancy. BMI is not used to assess weight during pregnancy.
• Children and young people. Adult categories do not apply. Children are assessed using BMI centile charts that account for age and sex, and other factors also matter when interpreting BMI.

What should I check alongside BMI?

Your waist measurement, compared with your height. Waist to height ratio is used alongside BMI to assess overall health risk, including central adiposity, and UK guidance encourages adults with a BMI below 35 to measure their own.

The target is easy to remember: keep your waist to less than half your height. A ratio of 0.5 to 0.59 indicates increased central adiposity, and 0.6 or above indicates high central adiposity with further increased health risks.

Measure midway between the bottom of your ribs and the top of your hips, which is usually just above the navel, breathing out naturally. Taken together, BMI and waist to height ratio tell you considerably more than either does alone. A healthcare provider may also use measures such as skinfold thickness when BMI and waist checks do not give the full picture.

What to do if your BMI is in the overweight range

The right response depends on where in the band you are and what else is true about your health. Here is a reasonable way to think about it.

If you are at risk of diabetes, losing around 5% to 7% may help reduce that risk.

Any next step should take account of possible health problems, and weight loss medicines are prescribed alongside diet advice rather than instead of it.

When does 27 become a clinical number?

A BMI of 27 can be relevant when assessing weight-management treatment, but there is no single BMI-27 threshold that applies to every medicine. Eligibility depends on the medicine being considered, weight-related health conditions, BMI, ethnicity-specific thresholds where applicable, and the person's overall clinical assessment.

Weight-related conditions can affect whether someone is considered for particular weight-management treatments. Examples include high blood pressure, abnormal cholesterol levels, type 2 diabetes, obstructive sleep apnoea and cardiovascular disease, although the exact criteria depend on the medicine and the relevant UK guidance.

This is worth knowing for a practical reason. Someone at a BMI of 28 who does not know whether they have raised blood pressure or raised blood sugar cannot answer the eligibility question, and neither can anyone else. That is an argument for having the checks done rather than guessing.

Meeting a threshold is not the same as being suitable for treatment. Treatment suitability depends on an individual clinical assessment, and your prescriber will determine the appropriate treatment. A high BMI should prompt a fuller assessment rather than be read on its own. If you want to understand which options might apply, an online consultation with UK registered prescribers is a reasonable place to start.

Should I try to lose weight safely if I am in this range?

That is a decision for you and a healthcare professional, and there is no single right answer for everyone in a band this wide.

If your waist measurement, blood pressure and blood tests are within healthy ranges and you are physically active, your BMI should be considered alongside the rest of your health rather than in isolation. If your waist is above half your height, or you have a weight related condition, reducing weight is likely to bring measurable benefit. If weight reduction is the goal, it is best to lose weight safely and steadily rather than quickly. If weight loss is appropriate for you, gradual and sustainable weight loss is generally preferable to rapid or extreme approaches.

Regular physical activity supports weight management, with at least 150 minutes of moderate-intensity aerobic activity per week recommended as a baseline. Adults should aim for regular physical activity, including at least 150 minutes of moderate-intensity activity a week, alongside muscle-strengthening activity on at least 2 days a week.

What is worth avoiding either way is a rapid or extreme approach. Sustainable lifestyle changes over months do more for the measurements that matter than anything done in a week. A balanced diet also helps support progress and overall health.

When to see a doctor

Book an appointment rather than treating this as a weight question if any of the following apply.

• Weight gain that has been rapid, over days or weeks, rather than gradual.
• Weight loss you did not intend or work for.
• Swelling of the ankles or legs, especially with breathlessness.
• Increasing thirst and passing urine more often than usual, particularly with blurred vision.
• Being told you stop breathing during sleep, or persistent daytime sleepiness.
• Persistent tiredness, feeling cold, or other symptoms alongside weight change, which may point to a thyroid or hormonal cause.

It is also reasonable to see someone if the number itself is causing you distress, or if thinking about your weight is taking up more of your attention than you would like.

Medical Disclaimer

This article is for general information and does not replace professional medical advice. BMI is a screening measure, not a diagnosis, and the categories described here cannot tell you whether you are healthy; BMI alone does not tell the whole story and may need context from a healthcare provider. Prescription only medicines should be used only under the supervision of an appropriately qualified prescriber, following a clinical assessment, and results vary between individuals. If you take a prescribed medicine, follow the patient information leaflet supplied with it, never take extra to make up for a missed dose, and do not stop a prescribed medicine without discussing it with the prescriber. Speak to a healthcare professional before making significant changes to your diet or activity, particularly if you have an existing health condition. Seek urgent medical attention for severe or rapidly worsening symptoms.