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 By Age — What's Healthy for You?
Weight ranges vary by age, height, and individual health factors — there's no single "ideal" weight that applies to everyone. In the UK, the NHS uses BMI (body mass index) as the primary screening tool to determine healthy weight ranges regardless of age. BMI categories are the same for all adults over 18, though ethnicity-adjusted thresholds apply for people of South Asian, Chinese, Black African, or Black Caribbean heritage. This guide explains how to find your healthy weight range and why age matters more for overall health context than for BMI calculation itself.
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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.
How BMI Determines Healthy Weight Ranges
The NHS BMI categories apply to all adults aged 18 and over, and they remain consistent throughout adulthood — there are no separate age-adjusted BMI ranges for older adults in the UK. However, age is relevant because older adults may have different health priorities and muscle composition.
- Healthy weight (BMI 18.5–24.9): Associated with lower risk of weight-related health conditions
- Overweight (BMI 25.0–29.9): Increased health risks, though age and fitness level also matter
- Obese (BMI 30+): Significantly elevated risk of type 2 diabetes, heart disease, and other conditions
To find your healthy weight range for your height, use our free BMI calculator above — it calculates instantly and shows your personal healthy weight band. You can also use our weight converter to switch between kg, stone, and pounds for easier UK context. For South Asian, Chinese, Black African, or Black Caribbean adults, healthier BMI ranges are lower (18.5–22.9 for healthy weight), reflecting higher metabolic health risks at standard BMI thresholds.
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.
Age, Weight Management, and Health Context
While BMI thresholds don't change with age, age itself influences weight management strategies and health outcomes. Younger adults may benefit from weight management for disease prevention, while older adults managing weight loss may focus on preserving muscle mass and maintaining bone strength. Regular physical activity becomes increasingly important with age to maintain muscle and metabolic health.
Key considerations: Metabolism naturally slows with age, meaning older adults may need fewer calories to maintain the same weight. Weight-related health conditions like type 2 diabetes and high blood pressure become more common with age, making healthy weight management progressively more important. If you're concerned about your weight in relation to your age and health, speak with your GP who can provide personalised guidance based on your individual medical history and fitness.
- 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 my healthy weight change as I get older?
No — NHS BMI categories remain the same throughout adulthood (18.5–24.9 for healthy weight). However, age affects metabolism, muscle mass, and health risks, so weight management strategies may differ. Your GP can advise what's appropriate for your individual circumstances.
What's the healthy weight range for a 5ft 8in adult?
For someone 5ft 8in (173cm), the healthy BMI range (18.5–24.9) equals approximately 55–74kg (8st 10lb–11st 10lb). Use our free BMI calculator above to calculate your exact healthy weight range based on your height and to convert between units instantly.
Are there different weight charts for men and women?
No — BMI categories are the same for all adults regardless of sex. However, body composition differs (women typically have higher body fat percentage at the same BMI), and pregnancy changes weight management entirely. Your GP can discuss what's healthy for you personally.
How do I use a weight height chart to check if I'm a healthy weight?
Find your height on the left side and your weight on the bottom, then see where they intersect. If it falls in the healthy BMI range (18.5–24.9 according to NHS guidelines), you're in the healthy zone. Our BMI calculator does this instantly — much faster and more accurate than paper charts.
What if my BMI is high but I feel healthy — should I still worry about weight?
BMI is a screening tool, not a definitive health measure — it doesn't account for muscle mass or fitness level. However, even without symptoms, excess weight increases health risks including type 2 diabetes and heart disease. Your GP can assess your individual health and discuss whether weight management is appropriate for you.
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.