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 120kg in Stone? UK Conversion & Health Context
120 kilograms is equivalent to 18 stone and 13 pounds in UK measurements. If you're wondering what this weight means for your health, it's useful to know how it translates to stone and to understand where it sits in relation to NHS healthy weight guidelines. Use our free weight converter above to switch between kg, stone, and lbs instantly, and explore your personal BMI and healthy weight range with our free BMI calculator.
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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.
120kg Conversion and Health Thresholds
120kg exact conversion:
- 120 kg = 18 stone 13 pounds (18st 13lbs)
- 120 kg = 264.6 lbs
To understand this weight in context, the NHS provides healthy weight ranges based on your height. At 120kg, most adults would be in the overweight or obese category according to NHS BMI guidelines, though this depends entirely on your height. For example, an adult of 5ft 11in (180cm) with a weight of 120kg would have a BMI of approximately 16.7, which falls in the healthy range. However, someone of average UK female height (5ft 3in / 160cm) at 120kg would have a BMI of around 30.3, which is in the obese category. The NHS recommends a healthy weight range of 18.5 to 24.9 BMI for most adults, though thresholds are lower for people of South Asian, Chinese, Black African, or Black Caribbean heritage.
Clinically BackedWeight Loss
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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.
How Weight Affects Health and Next Steps
Whether 120kg is a concern for your health depends on your individual circumstances, including your height, age, fitness level, and any existing health conditions. Your GP can provide personalised guidance on what your weight means for your wellbeing. If you're interested in weight management options, the NHS offers a weight loss pathway starting with self-help resources and digital tools, progressing to specialist services where prescription weight loss medications may be considered. Evidence-based weight loss approaches combine dietary changes with increased physical activity, and sustainable loss is typically around 0.5 to 1kg per week. Track your progress using our free progress tracker to monitor changes 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.
Is 120kg overweight or obese?
This depends on your height. 120kg gives a BMI of approximately 30 at 160cm (5ft 3in), which is obese, but a BMI of 26.7 at 180cm (5ft 11in), which is overweight. Use our BMI calculator to find your exact BMI and where you sit on the NHS health scale.
What's the healthy weight range for someone who is 120kg?
Healthy weight depends on height. At 160cm, healthy weight is 47–63kg; at 170cm, it's 53–71kg; at 180cm, it's 60–80kg. Use our free BMI calculator above to find the healthy range for your exact height.
How much weight would I need to lose to reach a healthy BMI?
This varies by height. At 160cm and 120kg, you'd aim for under 63kg (a loss of approximately 57kg). At 180cm and 120kg, you're already in the overweight range and may need to lose less. Your GP can discuss realistic, personalised targets.
Can I use weight loss medication if I weigh 120kg?
Prescription weight loss medications are available for adults with a BMI of 30 or above, or 27+ with weight-related health conditions like type 2 diabetes or high blood pressure. A prescriber will assess your individual eligibility through a clinical consultation. Our GLP-1 weight loss calculator can help you explore potential outcomes.
What's the best way to lose weight from 120kg?
Sustainable weight loss combines a calorie deficit (typically 500 kcal/day for 0.5kg/week loss) with increased physical activity and behaviour change. The NHS recommends losing no more than 0.5–1kg per week. Your GP can refer you to NHS weight management services or discuss personalised approaches.
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.