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
15.1 kg in Stone — Is This a Healthy Weight?
15.1 kilograms converts to 2 stone 5.2 pounds (2st 5.2lbs) using standard kg to stone conversion. Whether this weight is healthy depends entirely on your height. For an adult, the NHS defines a healthy weight based on your BMI (Body Mass Index), which combines your weight with your height. The same weight can be healthy for one person and overweight for another. Use our free BMI calculator above to check whether 15.1 kg falls in a healthy range for you personally.
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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 determine if 15.1 kg (2st 5.2lbs) is healthy, you need to know your height. Here are three concrete examples:
- Height 145 cm (4ft 9in): A weight of 15.1 kg gives a BMI of 7.2 — this would be dangerously underweight and would require medical attention.
- Height 155 cm (5ft 1in): 15.1 kg gives a BMI of 6.3 — also severely underweight, well below healthy range.
- Height 170 cm (5ft 7in): 15.1 kg gives a BMI of 5.2 — severely underweight across all heights.
For reference, the NHS healthy weight range for each height is shown in the table below. A healthy BMI sits between 18.5 and 24.9. At 15.1 kg, this weight is below the healthy range for all adult heights and would require GP guidance.
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.
What to Do If Your Weight Is Outside the Healthy Range
If you're significantly underweight, speak with your GP or healthcare professional — they can assess whether there's an underlying cause and recommend appropriate support. Underweight status can indicate malnutrition, medical conditions, or other health concerns requiring professional guidance.
Conversely, if you're concerned about being overweight, our free weight converter and BMI calculator can help you track where you stand. The NHS recommends losing weight at a rate of 0.5 to 1 kg per week for sustainable results. Remember: weight is just one health marker. Your GP can discuss your individual health context, including waist circumference and other factors that matter.
- 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.
What is 15.1 kg in stone and pounds?
15.1 kg equals 2 stone 5.2 pounds (2st 5.2lbs). To convert kilograms to stone, divide by 6.35029. This exact conversion is useful for UK health records and discussions with your GP.
Is 15.1 kg a healthy weight for an adult?
At 15.1 kg, this weight is significantly underweight for virtually all adult heights and falls well below NHS healthy weight thresholds. A healthy BMI (18.5–24.9) requires much higher weight at any adult height. Please consult your GP.
How do I check if my weight is healthy for my height?
Use our free BMI calculator above — it calculates your BMI instantly based on your weight and height. A BMI of 18.5 to 24.9 is considered healthy by the NHS. Your GP can also provide personalised guidance about what's healthy for you specifically.
What does BMI mean and why does it matter?
BMI (Body Mass Index) is weight in kg divided by height in metres squared. It's a screening tool used by the NHS to identify whether weight may pose health risks. However, BMI has limitations — it doesn't account for muscle mass or fat distribution, so always discuss results with your GP.
What should I do if I'm underweight?
If you're significantly underweight, contact your GP. They can investigate potential causes (nutritional deficiency, medical conditions, or other factors) and recommend appropriate support. Never attempt rapid weight gain without professional guidance.
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.