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 A Stone? — Understanding UK Weight Measurements
A stone is the traditional UK unit of weight measurement equal to exactly 14 pounds, or approximately 6.35 kilograms. It's still the standard way most UK adults describe their body weight, even though the NHS uses kilograms for clinical measurements. Understanding stone alongside kilogrammes helps you engage with UK health guidance, weight management conversations with your GP, and use our free weight converter tool to track your health progress effectively.
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.
Stone, Pounds, and Kilograms — How They Connect
One stone equals:
- Exactly 14 pounds (lbs)
- Approximately 6.35 kilograms (kg)
The term "stone" comes from historical trading when actual stones were used as counterweights on scales. Today, UK adults commonly describe their weight in stone and pounds — for example, "I weigh 11 stone 7 pounds" — while healthcare professionals use kilograms for precision and consistency with international guidelines. The NHS provides healthy weight guidance based on BMI, which can be calculated from any unit (stone, pounds, or kilograms). Our free weight converter above lets you switch between these measurements instantly. To find your healthy weight range, use our BMI calculator, which shows whether your current weight falls into the NHS healthy weight category (BMI 18.5–24.9) regardless of which unit you prefer.
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 Stones Matter for UK Health Management
Understanding stone is essential for UK health conversations. When discussing weight management with your GP, you'll often hear measurements in both stone and kilograms. NHS guidance on healthy weight uses BMI thresholds that apply equally whether you measure in stone or kg — what matters is the total weight relative to your height. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends different BMI thresholds due to higher health risks at lower weights. Whether you're tracking weight loss, understanding overweight and obesity definitions, or simply managing your health, knowing how to convert between stone and other measurements helps you engage fully with NHS health information and weight management resources.
- 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.
How many kilograms is one stone?
One stone equals approximately 6.35 kilograms. To convert stone to kg, multiply the number of stone by 6.35. For example, 10 stone = 63.5 kg. Use our free weight converter above for instant conversions between stone, pounds, and kilograms.
Is stone still used by the NHS?
The NHS primarily uses kilograms for clinical measurements and guidelines, but many UK patients and GPs still reference stone in everyday conversations. NHS healthy weight guidance is based on BMI, which works equally well regardless of whether you measure in stone, pounds, or kilograms.
What's the difference between stone and pounds?
One stone equals exactly 14 pounds. Stone is used as a larger unit for total body weight (e.g., "11 stone"), while pounds express the remainder (e.g., "11 stone 7 pounds" = 11.5 stone or 73 kg). Our weight converter tool handles all these conversions instantly.
How does stone relate to healthy weight guidance?
Your healthy weight range is determined by your BMI, which is calculated from your total weight and height. Whether you weigh yourself in stone, pounds, or kilograms, the same healthy BMI range (18.5–24.9) applies. Use our free BMI calculator to check whether your weight in stone falls into a healthy range for your height.
Can I track weight loss using stone?
Yes. Many UK adults prefer tracking weight loss in stone because it's familiar and easier to visualise progress (losing a full stone is a clear milestone). You can use our free progress tracker to log your weight in stone, pounds, or kilograms — whichever feels most natural for you — and watch your weight management journey unfold.
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.