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 8.5 stone in kilograms?
8.5 stone is equal to 53.98 kilograms (kg). This conversion uses the standard UK to metric weight measurement — one stone equals 6.35029 kg. If you're tracking your weight in different units or comparing your measurements against NHS health guidance, our free weight converter above makes it simple to switch between stone, pounds, and kilograms instantly. Understanding your weight in both metric and imperial measurements helps you engage with UK health information more confidently.
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.
8.5 Stone in Context — NHS Health Guidance
At 8.5 stone (53.98 kg), your healthy weight assessment depends on your height. Using NHS BMI guidelines, an adult at 8.5 stone would fall into the healthy weight category if they are around 5 feet 2 inches (157 cm) tall or shorter. For taller individuals, 8.5 stone would likely fall into the underweight range. The NHS defines a healthy BMI as between 18.5 and 24.9 — your personal healthy weight range can be calculated using our free BMI calculator on this page, which accounts for both your weight and height together. Remember that BMI is a screening tool and doesn't account for muscle mass or individual health variation.
- 8.5 stone = 53.98 kg (exactly)
- Healthy BMI range for most UK adults: 18.5–24.9
- For some ethnic backgrounds, the NHS recommends lower thresholds — ask your GP if this applies to you
- Weight alone doesn't tell the full health story — waist circumference and fitness level matter too
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.
Using the Weight Converter — Quick Reference
Converting between stone and kilograms is straightforward once you know the formula: divide kilograms by 6.35029 to get stone, or multiply stone by 6.35029 to get kg. For 8.5 stone, the calculation is 8.5 × 6.35029 = 53.98 kg. Our weight converter tool on this page handles all conversions instantly — including stone and pounds combined (e.g., 8 stone 7 lbs) into pure kilograms or vice versa. This is especially useful when reading UK health articles that use kg, since most NHS guidance and international health standards use metric measurements. Keep a note of your weight in both units for easy reference across different healthcare settings and fitness apps.
- 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.
Is 8.5 stone a healthy weight?
It depends on your height. 8.5 stone (53.98 kg) is a healthy weight for someone around 5 feet 2 inches or shorter. Use our free BMI calculator above to find your personal healthy weight range by entering your height and current weight. Your GP can also advise on what's healthy for your individual circumstances.
How do I convert stone to kg accurately?
Multiply the stone figure by 6.35029 to get kilograms. For 8.5 stone: 8.5 × 6.35029 = 53.98 kg. If you have stone and pounds (e.g., 8st 7lbs), use our weight converter on this page — it handles combined measurements instantly and accurately.
What's the difference between stone and kilogram measurements?
Stone is used primarily in the UK and Commonwealth countries for body weight. One stone equals exactly 14 pounds or 6.35029 kilograms. Most of the world and the NHS use kilograms. Understanding both units helps you engage with UK health guidance and international health information equally well.
Where does 8.5 stone fit on the NHS weight chart?
8.5 stone's category depends entirely on height. Check your BMI using our free calculator above — it positions your weight against NHS healthy ranges specific to your height. The NHS healthy weight band is a BMI of 18.5–24.9; South Asian, Chinese, and Black African/Caribbean adults may have different thresholds.
Should I track my weight in stone or kilograms?
Use whichever unit feels natural — UK GPs and NHS systems use kg, but many UK adults prefer stone for personal tracking. Our weight converter and progress tracker let you log in either unit and switch between them, so you can use what's most comfortable for your NHS health guide and fitness journey.
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.