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 My Right Weight? A UK Health Guide
Your "right weight" isn't one fixed number — it's a personalised healthy range based on your height, age, and overall health. Using NHS guidelines and established health metrics, MyWeightCheck helps you discover whether your current weight supports your wellbeing. Finding your right weight means understanding your healthy weight UK range, which varies from person to person depending on factors like muscle mass, genetics, and existing health conditions. This guide explains how to identify your personal healthy weight and why it matters for your long-term 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.
Understanding Your Healthy Weight Range
Your right weight is determined using BMI (Body Mass Index) alongside other health markers like waist circumference and overall fitness. According to NHS guidance, a healthy BMI falls between 18.5 and 24.9 for most adults. However, your ideal weight also depends on your height, frame size, and muscle composition.
- Use our free BMI calculator to identify where your current weight falls on the NHS scale
- A healthy weight UK range for your height can be calculated using the formula: healthy weight = BMI 18.5–24.9 × height (m)²
- For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, lower thresholds apply — NHS recommends starting at BMI 18.5–22.9
- Weight converters help you understand your weight in stone, pounds, or kilograms — all common UK measurements
Finding your right weight involves checking multiple factors, not just the number on the scales. Your GP can provide personalised guidance based on your medical history and health goals.
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 Your Right Weight Matters for Health
Reaching and maintaining your right weight significantly reduces your risk of type 2 diabetes, heart disease, high blood pressure, and certain cancers. Even a modest weight loss of 5–10% of your body weight can deliver measurable health benefits including better blood sugar control, improved mobility, and reduced joint strain.
Weight management isn't about achieving a number on the scales — it's about supporting your body's long-term health. If you're struggling to reach your healthy weight range, evidence-based approaches including lifestyle changes and, where appropriate, prescription weight loss medication prescribed by your GP or a licensed prescriber may help. Try our free progress tracker to monitor your weight loss journey over time.
- 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 considered a healthy weight in the UK?
According to NHS guidance, a healthy BMI for most UK adults is between 18.5 and 24.9. Your specific healthy weight range depends on your height — use our BMI calculator to find your personal range. For example, an adult who is 1.70m tall has a healthy weight range of approximately 53–72 kg (8st 5lbs–11st 4lbs). Your GP can discuss what's right for your individual circumstances.
How do I calculate my right weight using my height?
Use this formula: multiply your height in metres by itself, then multiply by 18.5 (lower healthy BMI) and 24.9 (upper healthy BMI). For someone 1.75m tall: 1.75 × 1.75 = 3.06. Lower range: 3.06 × 18.5 = 56.6 kg; upper range: 3.06 × 24.9 = 76.2 kg. Our free BMI calculator does this instantly — just enter your height and current weight.
Does my right weight change as I get older?
BMI categories remain the same across adulthood, but healthy weight management becomes more important with age because muscle naturally decreases. Maintaining your right weight helps prevent age-related conditions like diabetes, osteoarthritis, and heart disease. Your GP can advise whether your target weight needs adjustment based on your age and health status.
Is there a difference between "ideal weight" and "healthy weight"?
Yes. Healthy weight is based on BMI and health markers — it's a range supporting wellbeing. Ideal weight is more personal and varies based on muscle mass, frame size, and individual goals. Your right weight is the healthy range your GP recommends for you. The NHS weight management approach focuses on reaching a healthy weight rather than pursuing a specific "ideal" number.
Can I use weight converters to understand my right weight better?
Absolutely. Our free weight converter helps you understand your weight in kilograms, stone, or pounds — all relevant for UK health guidance. Converting between units helps you compare your weight against NHS healthy weight ranges more clearly. Combine the converter with our BMI calculator for a complete picture of your health metrics.
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.