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 21 Stone in Pounds?
21 stone is equal to 294 pounds (lbs). This conversion uses the standard UK measurement where 1 stone equals exactly 14 pounds. If you're checking your weight or need to understand measurements across different scales, our free weight converter above makes it easy to switch between stone, pounds, and kilograms instantly. Understanding your weight in different units helps with health planning and NHS guidance interpretation.
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.
How to Convert Stone to Pounds
Converting stone to pounds is straightforward using a simple formula: multiply the stone value by 14. So 21 stone × 14 = 294 pounds. This works because 1 stone is always equal to exactly 14 pounds — a fixed UK measurement standard. If you have stone and pounds combined (e.g., 21 stone 5 pounds), you would calculate: (21 × 14) + 5 = 299 pounds total. Our free weight converter tool above handles these calculations instantly, but understanding the method helps when you need quick mental conversions. The metric equivalent of 21 stone is approximately 133.4 kg. Whether you're tracking health metrics, checking NHS weight guidance, or simply curious about different measurement systems, having conversions readily available supports better health awareness.
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.
Weight Context and Health Information
At 21 stone (294 lbs / 133.4 kg), understanding your BMI and health context is important for NHS guidance purposes. Our free BMI calculator on this page can show you your personal BMI category based on your height — this is more informative than weight alone, as BMI accounts for both weight and height. For most UK adults, a BMI of 30 or above falls within the obese category and may warrant GP discussion about weight management options. If you're exploring weight loss support, speaking with your GP is the first step. They can assess your individual health needs and discuss evidence-based approaches, including lifestyle changes and, where appropriate, prescription weight management options like GLP-1 medications. 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.
How many pounds is 21 stone?
21 stone equals 294 pounds (lbs). To convert, multiply stone by 14 since 1 stone = 14 pounds exactly. This is the standard UK conversion used by the NHS, GPs, and all UK health services.
What is 21 stone in kilograms?
21 stone is approximately 133.4 kg. To convert stone to kilograms, multiply by 6.35029. Use our free weight converter for instant conversions between all three UK and metric measurements.
Is 21 stone considered overweight or obese?
Whether 21 stone indicates overweight or obesity depends on your height and BMI. Use our free BMI calculator above to find your personal BMI category. If you have health concerns, speak with your GP for personalised guidance.
How can I convert between stone and pounds easily?
Multiply stone by 14 for pounds, or divide pounds by 14 for stone. Our free weight converter tool on this page does this instantly for any value. It also converts to and from kilograms.
Why does the UK use stone for weight?
Stone is a traditional UK and imperial measurement still widely used by UK adults, GPs, and healthcare settings. The NHS uses both stone and kilograms. Our weight converter helps you switch between any units instantly.
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.