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 BMI Is 17.3 Kg in Stone?
17.3 kg converts to 2 stone 9.3 lbs in UK measurements. However, your BMI depends entirely on your height — the same weight gives very different BMI results for different people. Below, we show you what BMI 17.3 kg produces at six common heights, along with the NHS health category for each. Use our free BMI calculator above to find your exact BMI instantly, then check where you fall on the NHS health scale.
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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.
17.3 Kg BMI at Different Heights
17.3 kg is a very low body weight and typically falls into the underweight BMI category for most adults. Here's what BMI you'd have at different heights:
- At 150 cm (4ft 11in): BMI of 11.6 — underweight
- At 160 cm (5ft 3in): BMI of 10.8 — underweight
- At 170 cm (5ft 7in): BMI of 10.1 — underweight
- At 180 cm (5ft 11in): BMI of 9.5 — underweight
- At 190 cm (6ft 3in): BMI of 8.8 — underweight
If you're experiencing unintended weight loss or are concerned about being underweight, speak with your GP. Being significantly underweight can affect energy, immunity, and bone health. Use the weight converter on this page to see 17.3 kg expressed in different units for reference.
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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 BMI Categories and What They Mean
The NHS classifies BMI into five main health categories. A BMI below 18.5 is considered underweight and may indicate insufficient calorie intake or underlying health concerns. The healthy weight range is 18.5 to 24.9, while 25.0 to 29.9 is overweight, and 30.0 and above is obese.
It's important to note that BMI has limitations — it doesn't account for muscle mass, bone density, or where fat is stored on your body. Your GP can provide personalised health advice based on your individual circumstances, medical history, and overall fitness level, not just your BMI number alone.
- 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 17.3 kg in stone and pounds?
17.3 kg converts to 2 stone 9.3 lbs (or 2 stone and 9.3 pounds) using the standard UK weight conversion. To convert kilograms to stone, divide by 6.35029. This is a very light body weight for most adult heights.
Is 17.3 kg a healthy weight?
At 17.3 kg, you would be underweight for virtually any adult height — your BMI would fall well below 18.5. If this is your current weight, speak with your GP about whether it's appropriate for your age, height, and health. Unintended weight loss warrants medical assessment.
How do I use the BMI calculator for my exact height?
Enter your weight (17.3 kg) and your height into our free BMI calculator above. It will instantly show your personal BMI number and which NHS health category you fall into. This is much more accurate than using example heights.
What should I do if I'm underweight?
If you're underweight or experiencing unintended weight loss, contact your GP. They can check for underlying causes like medical conditions, nutritional deficiencies, or other health issues. Your GP may refer you to a dietitian for personalised nutritional advice.
Can I use this to convert other weights to stone?
Yes — use our free weight converter on this page to convert any kilogram weight to stone and pounds instantly. You can also use it to convert between kg, stone, and pounds for reference or health tracking purposes.
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.