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
Suggested Weight Calculator — Your Healthy Weight Range
A suggested weight calculator helps you find the healthy weight range for your height using NHS guidelines. Rather than a single "ideal" number, the NHS recommends a healthy weight range based on your height, age, and individual circumstances. This approach is more realistic than targeting one exact weight, and it aligns with modern weight management principles. MyWeightCheck provides free tools to calculate your personal healthy weight range and understand where you currently stand on the health spectrum.
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.
How to Calculate Your Healthy Weight Range
Your healthy weight range is determined by calculating a healthy BMI range between 18.5 and 24.9 for your height. The NHS uses this standard for UK adults. To find your range:
- Calculate the lower bound: multiply your height in metres by itself, then multiply by 18.5
- Calculate the upper bound: multiply your height in metres by itself, then multiply by 24.9
- The result is your healthy weight range in kilograms
For example, an adult who is 1.70m tall has a healthy weight range of approximately 53kg to 72kg (8st 5lbs to 11st 5lbs). Use our free BMI calculator above to instantly find your personal healthy weight range—simply enter your height and current weight, and the tool will show your BMI category and target range. For those of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends slightly lower thresholds starting at a BMI of 18.5 to 22.9, reflecting higher health risks at standard thresholds.
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.
Why a Range, Not a Single Target Weight?
A healthy weight range is more realistic than a single target because body composition varies—two people at the same height and weight can have very different amounts of muscle and fat. Muscle weighs more than fat, so athletes or very fit individuals may fall outside the "healthy" range despite being in excellent health. The NHS guidance focuses on health outcomes rather than appearance: losing even 5–10% of your body weight can reduce blood pressure, improve blood sugar control, and lower the risk of type 2 diabetes and heart disease. Our free weight converter helps you switch between kg, stone, and pounds so you can easily track progress in whichever unit you prefer. Set a range rather than obsessing over a single number, and focus on sustainable habits like balanced nutrition and regular physical activity.
- 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 healthy weight range for my height?
Your healthy weight range is based on a BMI of 18.5–24.9 for your height. Use our free BMI calculator on this page—enter your height and current weight, and it will instantly show your personal healthy weight range in both kilograms and stone. The calculator also tells you where you currently sit on the health spectrum.
How much weight should I aim to lose per week?
The NHS recommends losing 0.5–1 kg (1–2 lbs) per week for safe, sustainable weight loss. This typically requires a calorie deficit of around 500 kcal per day. Faster loss can result in muscle loss and is harder to maintain long-term. Focus on steady progress rather than rapid results.
Is BMI the only measure of healthy weight?
BMI is a useful screening tool but has limitations—it doesn't account for muscle mass, bone density, or where fat is stored. Other helpful measures include waist circumference (NHS recommends under 94cm for men, 80cm for women) and overall fitness level. Speak to your GP for a complete health assessment.
What if my healthy weight range seems too high or low?
Your healthy weight range is based purely on height and NHS BMI guidelines, not on appearance or personal preference. If you have concerns about your weight or health, speak to your GP. They can assess your individual circumstances, medical history, and any weight-related health conditions to give personalised advice.
Can I use this calculator if I'm pregnant or have a medical condition?
This calculator is for general adult health information. If you're pregnant, breastfeeding, have a diagnosed medical condition affecting weight, or take medications that influence weight, consult your GP or a healthcare professional before using weight loss strategies or setting new targets.
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.