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 Average Weight — UK Health Context
The average UK adult man weighs approximately 85.7 kg (13 stone 7 lbs), while the average UK adult woman weighs around 71.6 kg (11 stone 3 lbs). However, "average" doesn't necessarily mean "healthy." According to NHS guidelines, a healthy weight depends on your height and is based on your BMI — a measurement that divides your weight by your height squared. This guide explains healthy weight ranges, how average weight compares to ideal weight, and how to find what's right for your individual health.
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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.
Healthy Weight Range by BMI — The NHS Framework
The NHS defines healthy weight using BMI (Body Mass Index). A healthy BMI is between 18.5 and 24.9, and the weight you need to achieve this depends entirely on your height.
Example healthy weight ranges:
- At 5ft 4in (163cm): healthy weight is approximately 50–67 kg (7st 10lbs – 10st 7lbs)
- At 5ft 8in (173cm): healthy weight is approximately 55–74 kg (8st 9lbs – 11st 8lbs)
- At 5ft 10in (178cm): healthy weight is approximately 58–79 kg (9st 1lb – 12st 5lbs)
These ranges assume an adult of European heritage. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends lower thresholds — a healthy BMI starts at 18.5 but healthy weight may be reached at BMI 22.9 rather than 24.9, due to increased health risks at higher BMI levels in these populations.
Use our free BMI calculator above to check your personal healthy weight range instantly based on your exact height.
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.
Average vs. Ideal — Understanding The Difference
Average weight is what most people weigh; ideal weight is what supports good health. Because the average UK adult is overweight or obese (around 63% of UK adults fall into these categories), the statistical average is not a health target. Your ideal weight should be based on your BMI, not on what others weigh.
Factors that affect your ideal weight include your age, sex, frame size, muscle mass, and any medical conditions. This is why two people of the same height can have different healthy weight ranges. The healthy weight calculator on this page takes your exact height into account, giving you a personalised BMI-based range rather than relying on population averages. Aim for the upper or lower end of the healthy BMI range depending on your body composition and how you feel.
- 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 for a UK woman?
The average UK adult woman weighs approximately 71.6 kg (11 stone 3 lbs). However, a healthy weight varies by height. Use the BMI calculator on this page to find your personal healthy weight range — it will be higher or lower depending on how tall you are.
Is average weight the same as healthy weight?
No. Average weight reflects what most people actually weigh; healthy weight is based on BMI and health risk. Because over 60% of UK adults are overweight, the average has shifted above the healthy range. Your personal ideal weight should be guided by your BMI and GP advice, not population statistics.
What does NHS say about healthy weight?
The NHS defines healthy weight as a BMI between 18.5 and 24.9. For South Asian, Chinese, Black African, and Black Caribbean adults, the upper threshold is lower (BMI 22.9) due to higher health risks at the same BMI. Your GP can give personalised guidance based on your individual health.
How do I calculate my ideal weight from my height?
Use the BMI calculator on this page — enter your height and it shows your healthy weight range instantly. Alternatively, multiply your height in metres by itself, then multiply by 18.5 (lower bound) and 24.9 (upper bound) to find your ideal weight range in kg.
Why does healthy weight vary so much between people?
Healthy weight depends on height, age, sex, muscle mass, and genetics. Two people of the same height may have different ideal weights if one has more muscle (muscle is denser than fat). This is why BMI is based on height, not a fixed number — and why the progress tracker helps monitor changes beyond just the scale.
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.