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 8.5 kg in Stones?
8.5 kilograms is equal to 1 stone and 5.4 pounds (1st 5.4lbs). This conversion uses the standard metric to imperial weight formula used across the UK. Whether you're checking a baby's weight, tracking health metrics, or converting measurements for a recipe, our free weight converter above makes it simple to switch between kg, stone, and pounds instantly. Use our BMI calculator to understand how this weight relates to health guidelines at different heights.
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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.
8.5 Kg to Stone Conversion Formula and Table
To convert 8.5 kilograms to stone, divide the kilogram value by 6.35029. The formula is straightforward: 8.5 kg ÷ 6.35029 = 1.34 stone, which equals 1 stone 5.4 lbs.
Here's a quick reference table showing weights near 8.5 kg in both metric and imperial measurements:
- 7 kg = 1st 1.8 lbs
- 7.5 kg = 1st 3.6 lbs
- 8 kg = 1st 5.4 lbs
- 8.5 kg = 1st 5.4 lbs
- 9 kg = 1st 7.2 lbs
- 9.5 kg = 1st 9.1 lbs
- 10 kg = 1st 10.9 lbs
Remember, 1 stone always equals exactly 14 pounds, so you can verify conversions using this constant ratio when working with kilos in stone.
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.
8.5 Kg BMI and Healthy Weight Context
At 8.5 kg, this weight is typically seen in babies (around 8–12 months old) or very young children. For adults, 8.5 kg would represent severe underweight status and would warrant discussion with a GP. Adult healthy weight ranges vary significantly by height — for example, an adult of 5ft 6in (168 cm) should typically weigh between 54–72 kg to fall within the healthy BMI range of 18.5–24.9. Use our free BMI calculator above to check what a healthy weight range is for your specific height and to understand your personal health context. If you have concerns about weight at any age, your GP can provide personalised guidance.
- 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 8.5 kg to stones and pounds?
Divide 8.5 by 6.35029 to get 1.34 stone. This equals 1 stone and 5.4 pounds. Alternatively, multiply 8.5 by 2.20462 to get 18.7 pounds, then divide by 14 (pounds per stone) to confirm. Our weight converter above does this instantly for you.
Is 8.5 kg a healthy weight for an adult?
8.5 kg is far below healthy weight for any adult and would indicate severe underweight status. A healthy adult weight depends on height — typically between 50–85 kg for most UK adults. Your GP can advise if you have weight concerns.
What does 8.5 kg equal in pounds only?
8.5 kg equals approximately 18.7 pounds (or 18lb 11oz). To convert any kilogram value to pounds, multiply by 2.20462. For reference, 1 kg = 2.20462 lbs.
How do I use the weight converter to check other values?
The weight converter tool on this page lets you enter any weight in kg, stone, or pounds and instantly see the equivalent in other units. It's helpful for recipes, health tracking, or understanding measurements across different regions.
What is my healthy weight range at my height?
Healthy weight ranges depend on your height and sex. Use our free BMI calculator above — enter your height and current weight to see if you fall within the healthy range (BMI 18.5–24.9 for most adults). For South Asian or other backgrounds, lower thresholds may apply per NHS 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.