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's a Normal Weight for Adults in the UK?
There's no single "normal" weight that applies to everyone — it depends on your height, age, sex, and body composition. However, the NHS provides a healthy weight range based on BMI (body mass index), which gives you a personalised target. A healthy weight is one where your BMI falls between 18.5 and 24.9. What matters most is whether your weight supports good health, reduces disease risk, and helps you feel energetic and confident. Our free BMI calculator helps you find your personal healthy weight range instantly.
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 Healthy Weight Ranges in the UK
The NHS healthy weight range is based on your height and BMI (body mass index), which divides weight by height squared. According to NHS guidance, a healthy BMI is between 18.5 and 24.9. For example, an adult who is 5ft 8in (173cm) tall has a healthy weight range of approximately 55 to 75 kg (8st 7lbs to 11st 10lbs). However, BMI has limitations — it doesn't distinguish between muscle and fat, so athletes or people with high muscle mass may have a higher BMI despite being healthy. Waist circumference is also important: men should aim for under 94cm (37in), and women under 80cm (31.5in) for reduced health risk. Use our free weight converter to see your weight in both metric and imperial measurements, making it easy to track where you fall on the healthy range.
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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.
How Weight Varies by Individual Factors
Normal weight isn't one-size-fits-all. Age, genetics, muscle mass, bone density, and ethnic background all affect your ideal weight. The NHS recognises this — adults of South Asian, Chinese, Black African, or Black Caribbean heritage have slightly lower healthy BMI thresholds (18.5 to 22.9) because they face higher health risks at lower weights. Pregnancy, hormonal changes, and certain medical conditions also influence weight. Rather than aiming for a specific number, focus on whether you feel healthy, energetic, and free from weight-related health problems like high blood pressure or type 2 diabetes. Your GP can provide personalised guidance based on your individual health picture, not just a number on the scales.
- 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's the average weight of a UK adult?
According to Office for National Statistics data, the average UK adult man weighs approximately 85.7 kg (13st 7lbs) and is 175.3 cm tall, giving an average BMI of 27.9. The average UK adult woman weighs approximately 71.6 kg (11st 3lbs) and is 161.6 cm tall, with an average BMI of 27.4. However, average does not mean healthy — both these figures fall into the overweight category.
How do I know if my weight is normal for my height?
Use the NHS healthy weight ranges based on your height. Our BMI calculator on this page will instantly show you your BMI and whether it falls in the healthy range (18.5–24.9). For personalised advice specific to your health conditions or family history, speak to your GP.
Does normal weight mean the same thing for men and women?
The healthy BMI range (18.5–24.9) is the same for both men and women. However, healthy weight ranges differ because men and women typically have different heights and body compositions. A healthy weight for a 5ft 10in man would be different from a healthy weight for a 5ft 4in woman, even though both might have the same BMI.
Is there a difference between normal weight and ideal weight?
Yes. Normal weight refers to what's statistically average in a population. Ideal weight is what's healthiest for you specifically, based on your height, age, health conditions, and genetics. Your ideal weight may be lower or higher than the statistical average, but it should fall within the NHS healthy BMI range.
What if my weight is above the healthy range — what should I do?
If your BMI is above 25, consider speaking to your GP about weight management options. This might include dietary changes, increased physical activity, or structured weight management support through the NHS. Your GP can also assess whether prescription weight loss support might be appropriate alongside lifestyle changes.
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.