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
Body Weight Index Table — UK Health Guidance
A body weight index table helps you understand where your current weight sits in relation to healthy ranges for your height. In the UK, the NHS uses BMI (Body Mass Index) as the primary screening tool, with tables that categorise weights from underweight through to severely obese. These tables are especially useful because they account for different heights — the same weight can mean very different things depending on whether you're 5ft or 6ft tall. This guide explains how to use UK-specific weight tables and what your results mean for your health.
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.
Understanding UK BMI Weight Tables
The NHS provides standardised BMI weight tables that categorise adults into five main groups based on their weight and height. A healthy BMI is between 18.5 and 24.9, which is the target range for most UK adults. Between 25 and 29.9 is classified as overweight, while 30 and above is obese. These tables work by dividing weight in kilograms by height in metres squared, though you don't need to calculate manually — our free BMI calculator above can work this out instantly. Importantly, the NHS recommends lower BMI thresholds for adults of South Asian, Chinese, Black African, and Black Caribbean heritage, as these groups face higher health risks at lower weights. This means a BMI of 23 might be a concern for someone of South Asian background but fall within the healthy range for other populations. Understanding your position on these tables gives you context for having conversations with your GP about weight management and health.
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.
Using Weight Tables for Health Guidance
Body weight index tables are most useful when combined with other health markers. Your BMI alone doesn't account for muscle mass, bone density, or where fat is stored — waist circumference is equally important. The NHS recommends that men keep waist circumference below 94cm (37 inches) and women below 80cm (31.5 inches) to reduce health risks. Weight tables also don't account for age, medication effects, or individual health conditions. If you're concerned about your weight or health, your GP can provide personalised guidance beyond what any table shows. You can also track changes over time using our free progress tracker alongside our weight converter tool to switch between stone, pounds, and kilograms as you monitor your journey.
- 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 a body weight index table used for?
Body weight index tables categorise weight ranges based on height to screen for health risks. In the UK, the NHS uses BMI tables to identify whether adults fall into healthy, overweight, or obese ranges. These tables help guide conversations with your GP and highlight whether weight-related health intervention might be appropriate.
What BMI range is healthy according to NHS guidance?
The NHS defines a healthy BMI as 18.5 to 24.9 for most UK adults. However, adults of South Asian, Chinese, Black African, or Black Caribbean heritage have lower recommended thresholds of 18.5 to 22.9, as these groups have higher cardiovascular and diabetes risk at the same BMI levels.
Does BMI tell the whole story about my weight and health?
No — BMI is a useful screening tool but has limitations. It doesn't distinguish between muscle and fat, doesn't account for where fat is stored, and varies with age and medication. Waist circumference, overall health markers, and individual circumstances matter just as much. Your GP can provide personalised assessment.
How can I find my position on a body weight index table?
Find your height in the left column and your weight along the top, then cross-reference to find your category. Alternatively, use our free BMI calculator above — it works out your exact BMI in seconds and tells you which category you fall into according to NHS guidelines.
What should I do if my weight falls in the overweight or obese category?
Start by speaking with your GP, who can assess your individual health and discuss options. The NHS supports a gradual approach of about 0.5–1kg per week through diet and physical activity. Prescription weight management support is available through NHS specialist services for eligible adults, or you can explore private options with a licensed prescriber.
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.