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 27.5 Kg In Stone? BMI & Health Context
27.5 kg is equivalent to 4 stone 5.5 lbs in UK measurements. However, whether this weight is healthy depends entirely on your height. Your BMI — the relationship between your weight and height — determines where you fall on the NHS health scale. Use our free BMI calculator above to find your personal BMI instantly, then read on to understand what it means for your health.
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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.
27.5 Kg BMI At Different Heights
To convert 27.5 kg to stone, divide by 6.35, giving you 4 stone 5.5 lbs. However, this weight alone tells you nothing about health — height matters enormously. Here's how 27.5 kg calculates across common UK heights:
- At 150 cm (4ft 11in): BMI 18.3 — healthy weight
- At 160 cm (5ft 3in): BMI 10.8 — healthy weight
- At 170 cm (5ft 7in): BMI 9.5 — healthy weight
- At 175 cm (5ft 9in): BMI 9.0 — healthy weight
- At 180 cm (5ft 11in): BMI 8.5 — healthy weight
At 27.5 kg, you fall well into the healthy weight range at all typical adult heights. This weight is particularly common for children and young teenagers rather than adults. If you're an adult at this weight, your GP may want to explore whether this is right for you.
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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.
Understanding BMI Categories & Limitations
The NHS divides BMI into clear categories: healthy weight (18.5–24.9), overweight (25–29.9), obese (30–34.9), and severely obese (40+). At 27.5 kg, your BMI is well below these thresholds, but BMI has important limitations. It doesn't distinguish between muscle and fat, doesn't account for where fat is stored, and doesn't reflect age or ethnicity. For adults of South Asian, Chinese, Black African, or Caribbean heritage, the NHS recommends lower BMI thresholds due to higher health risks at the same weight. Use our free weight converter to check your measurements in different units, and speak with your GP if you have concerns about your weight.
- 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 27.5 kg to stone and pounds?
Divide 27.5 by 6.35 to get stone. 27.5 ÷ 6.35 = 4.34 stone. The 0.34 stone converts to 4.76 pounds, so 27.5 kg equals approximately 4 stone 5.5 lbs. Our weight converter above makes this instant and accurate across all units.
Is 27.5 kg a healthy weight for an adult?
27.5 kg is very low for an adult and typically falls into the underweight category. A healthy weight for adults depends on height, but 27.5 kg would give a BMI below 18.5 at most adult heights. If you're an adult at this weight, discuss it with your GP to ensure it's appropriate for your individual health.
What BMI does 27.5 kg give at 170 cm?
At 170 cm (5ft 7in), 27.5 kg gives a BMI of 9.5, which is well below the healthy weight range of 18.5–24.9. This indicates very low body weight relative to height. Use our BMI calculator above to check your personal BMI at your exact height.
Should I be concerned if I weigh 27.5 kg?
If you're an adult weighing 27.5 kg, this is significantly below healthy weight ranges and warrants discussion with your GP. If you're a young person or child, BMI categories are different — children use age and sex-specific charts. Your GP can assess whether your weight is appropriate for your age, height, and individual health.
How does 27.5 kg compare to average UK weight?
The average UK adult woman weighs around 71.6 kg and the average UK adult man around 85.7 kg. At 27.5 kg, you'd be approximately 38% of average adult female weight and 32% of average adult male weight. This reinforces that 27.5 kg is very low for a typical adult and should be discussed with your healthcare provider.
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.