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's Your BMI at 90.9 Kg?
At 90.9 kg, your BMI depends entirely on your height. This weight converts to 14 stone 3.1 lbs in UK measurements. Whether this weight is healthy for you depends on how tall you are — the same weight gives a completely different BMI reading at 5ft 6in versus 6ft 2in. Below you'll find what BMI this weight gives at common UK heights, plus where each falls in the NHS categories. Use our free BMI calculator above to check your exact BMI instantly.
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.
90.9 Kg BMI at Different Heights
Here's what a weight of 90.9 kg means for your BMI across common UK heights:
- At 160 cm (5ft 3in): BMI 35.5 — Obese (Class II)
- At 165 cm (5ft 5in): BMI 33.4 — Obese (Class I)
- At 170 cm (5ft 7in): BMI 31.4 — Obese (Class I)
- At 175 cm (5ft 9in): BMI 29.7 — Overweight
- At 180 cm (5ft 11in): BMI 28.0 — Overweight
- At 185 cm (6ft 1in): BMI 26.6 — Healthy weight
To convert kilograms to stone for context, 90.9 kg equals approximately 14 stone and 3 pounds. Use our weight converter to switch between metric and imperial measurements instantly.
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.
Understanding BMI Categories and Limitations
According to NHS guidelines, a healthy BMI is 18.5 to 24.9 for most UK adults. At 90.9 kg, you're likely in the overweight or obese range depending on your height. However, BMI is just a screening tool — it doesn't account for muscle mass, bone density, or where fat is stored. An athletic person with significant muscle may have a high BMI but low body fat. If you're South Asian, Chinese, Black African, or Black Caribbean, the NHS recommends lower thresholds: healthy BMI starts at 18.5 but moves to 22.9 as the upper limit. Your GP can provide personalised health advice based on your complete picture.
- 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 90.9 kg in stone and pounds?
90.9 kg converts to 14 stone and 3.1 pounds (often written as 14st 3lbs). To convert kilograms to stone, divide by 6.35029. Use our free weight converter above for instant conversions between kg, stone, and pounds.
Is 90.9 kg overweight or obese?
At 90.9 kg, whether you're overweight or obese depends on your height. At 5ft 7in you'd be obese; at 6ft 1in you'd be in the healthy weight range. The NHS BMI calculator on this page shows your exact category based on your height.
What should I weigh for a healthy BMI?
For a healthy BMI (18.5–24.9), your weight depends on your height. At 170 cm (5ft 7in), healthy weight is roughly 53–72 kg. Use our BMI calculator to find your personal healthy weight range based on your exact height.
Does BMI tell the whole story about health?
No — BMI is a useful screening tool but has significant limitations. It doesn't distinguish between muscle and fat, doesn't account for where fat is stored (waist measurement matters too), and may not be accurate for elderly people or very muscular individuals. Your GP can assess your complete health picture.
Can I lose weight safely from 90.9 kg?
Yes. The NHS recommends losing 0.5–1 kg per week for sustainable results, typically through a modest calorie deficit alongside increased physical activity. For personalised guidance on weight loss strategies or whether weight loss medication might be suitable, speak with your GP or a qualified healthcare professional.
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.