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
Weight Height Chart According to Age — UK Guidance
There is no single "ideal" weight for a given height and age — healthy weight depends on factors including muscle mass, bone density, and individual health. However, the NHS uses BMI (Body Mass Index) to assess whether weight falls within a healthy range for a given height, and this applies consistently across adult age groups. Use our free BMI calculator above to check your personal range, or read on for UK health guidance on healthy weight by height.
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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.
NHS Healthy Weight Ranges by Height
The NHS defines a healthy BMI range of 18.5 to 24.9 for all UK adults, regardless of age. This means the healthy weight range for a given height stays the same whether you are 25 or 65 — what changes with age is metabolism, activity level, and muscle mass, which affect how easily weight is gained or lost.
- At 5ft 4in (163cm): healthy weight range is approximately 7st 10lbs to 10st 3lbs (49–65kg)
- At 5ft 6in (168cm): healthy weight range is approximately 8st 2lbs to 10st 13lbs (52–69kg)
- At 5ft 8in (173cm): healthy weight range is approximately 8st 10lbs to 11st 10lbs (55–74kg)
- At 5ft 10in (178cm): healthy weight range is approximately 9st 3lbs to 12st 8lbs (59–80kg)
For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends a slightly lower healthy BMI threshold: 18.5 to 22.9. This is because these groups face higher health risks related to obesity at the same BMI levels. Use our free weight converter to switch between kg, stone, and pounds 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.
Weight by Age — What Changes and What Doesn't
Healthy weight ranges do not change with age according to NHS guidelines — a BMI of 18.5–24.9 is healthy at 20, 40, and 70. However, maintaining a healthy weight often becomes more challenging with age due to declining muscle mass, reduced physical activity, and hormonal changes. Older adults may also have different health considerations — for example, being very underweight in later life can increase fracture risk, so discussions with your GP are important.
For children and teenagers, weight assessment is completely different — the NHS uses age and sex-specific growth charts, not adult BMI categories. If you are concerned about a young person's weight, speak to your GP or use the NHS Healthy Weight Calculator for children. Track your own weight progress using our free progress tracker to monitor changes over time and stay motivated.
- 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.
Does healthy weight change as you get older?
No — according to NHS guidelines, a healthy BMI of 18.5–24.9 applies to all adults regardless of age. However, maintaining a healthy weight often becomes harder with age due to changes in metabolism and activity levels. Your GP can advise on your individual situation.
Why are BMI thresholds different for some ethnic groups?
Research shows that South Asian, Chinese, Black African, and Black Caribbean adults face higher health risks at lower BMI levels. The NHS therefore recommends they aim for a BMI of 18.5–22.9 rather than 18.5–24.9 to reduce risk of type 2 diabetes and cardiovascular disease.
Can I use the same weight height chart for my teenager?
No — children and teenagers use different assessment methods. The NHS uses age and sex-specific growth centile charts, not adult BMI categories. Speak to your GP or school nurse for guidance on healthy weight for a young person.
What if my healthy weight range is very wide?
Healthy weight ranges vary by individual factors including muscle mass and frame size. The ranges given are guidelines only. Your GP can discuss what a healthy weight means for your specific circumstances and health goals.
How do I calculate my healthy weight for my height?
Use our free BMI calculator above — it instantly shows your healthy weight range based on your height. Alternatively, multiply your height in metres by itself, then multiply by 18.5 and 24.9 to get the lower and upper healthy weight in kilograms.
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.