The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
Free tracker included with every download this week
What Is The Overweight BMI?
The overweight BMI range according to NHS guidelines is 25.0 to 29.9. This falls between a healthy weight and obesity. If your BMI falls in this range, your GP may recommend lifestyle changes to reduce health risks. It's important to understand that BMI is just one health indicator — other factors like waist measurement and overall fitness also matter. Use our free BMI calculator above to check where you stand, and explore what this means for your individual health situation.
10,000+ calculations today · NHS-aligned thresholds · 100% free
Calculate Your BMI Instantly
Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
Understanding The Overweight BMI Range And Categories
The overweight BMI range is 25.0 to 29.9 according to NHS health guidelines. This sits between the healthy weight category (18.5–24.9) and obesity (30.0 and above). To calculate your BMI, divide your weight in kilograms by your height in metres squared — or use our BMI calculator above for gradual improvement.
Within the overweight category, there are gradations of health risk. A BMI of 25 carries less risk than a BMI of 29.9, though both technically fall into the overweight band. Your GP may offer guidance on lifestyle changes if your BMI is in this range, particularly if you also have weight-related health conditions like high blood pressure or type 2 diabetes. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends lower thresholds — overweight may begin at BMI 23.0 for these groups due to higher cardiovascular risk at lower weights.
Understanding your BMI range UK standards helps you take informed steps towards better health. You can also use our weight converter to track progress in your preferred units.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
BMI Limitations And What Else Matters
BMI limitations are important to understand. BMI does not distinguish between muscle and fat — athletes or people with high muscle mass may have a BMI in the overweight range despite having low body fat. BMI also ignores where fat is stored; excess weight around the stomach carries greater health risk than weight distributed elsewhere. The NHS therefore recommends measuring waist circumference alongside BMI: for men, over 94cm (37 inches) indicates increased risk; for women, over 80cm (31.5 inches) signals increased risk.
If you're in the overweight category, a GP conversation is valuable. They can assess your individual health picture, including blood pressure, blood sugar, and family history. Modest lifestyle changes — around 5–clinically studied weight loss — can significantly improve health markers even if you remain in the overweight range.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
What is the exact overweight BMI threshold?
The overweight BMI range starts at 25.0 and extends to 29.9 according to NHS guidelines. A BMI of exactly 25.0 marks the beginning of the overweight category, whilst 30.0 and above is classified as obese. These thresholds are the same for all adults regardless of age or sex.
Should I be concerned if my BMI is in the overweight range?
Being in the overweight range indicates increased health risk compared to healthy weight, but doesn't mean you have a health problem. Your individual risk depends on many factors: waist measurement, fitness level, blood pressure, blood sugar, and family history. Your GP can give you personalised guidance based on your complete health picture.
How is overweight BMI different from healthy weight BMI?
Healthy weight BMI is 18.5–24.9, whilst overweight is 25.0–29.9. A BMI in the overweight range suggests your weight may increase risk of certain health conditions compared to healthy weight, though individual risk varies. Even modest weight loss can reduce these risks.
Do ethnicity-adjusted BMI thresholds change the overweight category?
Yes. For South Asian, Chinese, Black African, and Black Caribbean adults, the NHS recommends lower thresholds. For these groups, overweight begins at BMI 23.0 (instead of 25.0) because research shows higher cardiovascular risk at lower BMIs. Your GP can advise whether adjusted thresholds apply to you.
Can I use the BMI formula to calculate my overweight status myself?
Yes. The BMI formula is weight (kg) divided by height (metres) squared. However, our free BMI calculator on this page calculates it instantly and tells you which category you fall into, making it much easier than a UK pharmacy calculation.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.