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
BMI Index Calculator for Men — How It Works
A body mass index (BMI) calculator for men helps you understand whether your weight is in a healthy range for your height. Our free BMI calculator above gives you an gradual improvement using the standard formula — and it's aligned with NHS guidelines so you get UK-specific health context. BMI is a useful starting point for understanding your health, though it's important to know its limitations and what the numbers actually mean for you personally.
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.
How to Calculate BMI and Understand Your Range
The BMI formula is straightforward: divide your weight in kilograms by your height in metres squared (kg ÷ height(m)²). For example, a man who is 1.75m tall and weighs 85kg has a BMI of approximately 27.8, which falls into the overweight category.
The NHS BMI categories for men are:
- Below 18.5 = Underweight
- 18.5–24.9 = Healthy weight
- 25.0–29.9 = Overweight
- 30.0–34.9 = Obese (Class I)
- 35.0–39.9 = Obese (Class II)
- 40.0+ = Severely obese (Class III)
For men of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends lower thresholds — a healthy weight range starts at 18.5 but overweight begins at 23.0 instead of 25.0, because these groups face higher cardiovascular and diabetes risk at the same BMI levels. Use our free BMI calculator above to check your personal result 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.
BMI Limitations and What Else Matters
BMI does not distinguish between muscle and fat. A man with significant muscle mass may have a high BMI but low body fat — so BMI alone doesn't tell the whole story. Waist circumference is equally important: for men, a waist over 94cm (37 inches) indicates increased health risk, and over 102cm (40 inches) indicates high risk, regardless of BMI.
Your GP can assess your individual health in context — including blood pressure, cholesterol, fitness level, and family history. If you're concerned about your weight or health, a conversation with your GP is always the best next step. You can also use our free weight converter to understand your weight in different units, and track changes over time with our progress tracker.
- 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 healthy BMI for a man in the UK?
According to NHS guidelines, a healthy BMI for men is between 18.5 and 24.9. However, for men of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends a healthy range of 18.5 to 22.9 due to higher health risks at higher BMIs in these populations.
Is BMI accurate for men with muscle?
No. BMI doesn't distinguish between muscle and fat, so muscular men may have a high BMI despite low body fat. Waist circumference is a better indicator in these cases — over 102cm (40 inches) suggests increased health risk for men.
Can I use a BMI calculator for weight loss planning?
Yes. Your BMI helps identify whether you're in a healthy range. If weight loss is needed, our free GLP-1 weight loss calculator can help estimate potential results with lifestyle changes or prescription medication if appropriate.
Does BMI change with age?
The BMI formula doesn't change with age, but health risks associated with the same BMI may change. Older men may benefit from a slightly higher BMI for bone health. Your GP can advise on what's right for you personally.
What should I do if my BMI is high?
Start by discussing your health with your GP. Small changes — like reducing portion sizes and increasing activity — can help. Your GP can also assess whether prescription weight loss treatment might be appropriate for you based on your overall health.
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.