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
Is 86.5kg in Stone a Healthy Weight?
86.5kg converts to 13 stone and 7 pounds. Whether this weight is healthy depends entirely on your height. For a person who is 1.75m (5ft 9in) tall, 86.5kg is in the overweight category. However, for someone who is 1.90m (6ft 3in) tall, the same weight falls within a healthy range. Use our free BMI calculator above to check your personal BMI instantly and see where you fall on the NHS health spectrum.
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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 Ranges by Height
To understand whether 86.5kg is healthy for you, we need to look at your height. The NHS uses BMI (body mass index) to determine healthy weight ranges, calculated as weight divided by height squared. A healthy BMI is between 18.5 and 24.9.
Three examples showing how the same weight (86.5kg) falls differently:
- At 1.70m (5ft 7in): BMI = 29.9 (overweight — just below obese threshold)
- At 1.80m (5ft 11in): BMI = 26.7 (overweight but closer to healthy range)
- At 1.90m (6ft 3in): BMI = 23.9 (healthy weight)
For each height, healthy weight ranges vary significantly. Use our weight converter to switch between metric and imperial measurements, then cross-check with your height using the BMI calculator on this page to find your personal healthy range.
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.
NHS Guidance and What to Do Next
If you're outside the healthy range: The NHS recommends a sustainable approach to weight management. This includes gradual, realistic changes rather than crash dieting. A healthy rate of weight loss is approximately 0.5 to 1kg per week.
Waist measurement also matters. Even if your BMI is borderline, your GP may assess waist circumference: over 94cm (37 inches) for men or 80cm (31.5 inches) for women indicates increased health risk. Your GP can discuss personalised health strategies with you, which may include lifestyle changes, dietary adjustments, or — if appropriate — referral to specialist weight management services. Non-judgmental support is always available.
- 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 do I convert 86.5kg to stone and pounds?
86.5kg converts to 13 stone and 7 pounds. To calculate: divide kg by 6.35 for stone, then multiply the decimal remainder by 14 for pounds. Our free weight converter on this page does this instantly for any weight.
What's my healthy weight if I'm 1.80m tall?
At 1.80m, a healthy BMI range is 18.5–24.9, which means a healthy weight range of approximately 60–80kg (9st 6lbs to 12st 8lbs). At 86.5kg, you'd be in the overweight category. Your GP can discuss personalised targets.
Is 86.5kg overweight for everyone?
No. Whether 86.5kg is overweight depends on your height and age. For someone 1.90m tall, it's healthy. For someone 1.65m tall, it's obese. This is why height matters — always check your BMI relative to your height using our BMI calculator.
What should I do if my weight is outside the healthy range?
Start with sustainable changes: reduce calories slightly, increase physical activity, and speak with your GP for personalised advice. The NHS recommends losing 0.5–1kg per week. Your GP can refer you to weight management services if needed and discuss all available options with you.
Does waist measurement matter as much as weight?
Yes. The NHS recommends checking both BMI and waist circumference, as fat distribution affects health risk. Even at a borderline BMI, excess abdominal fat increases cardiovascular risk. Your GP can assess both measurements during a health review.
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.