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
Understanding Body Fat Measured in Pounds
Body fat measured in pounds (lbs) refers to the total weight of fatty tissue in your body. Unlike total body weight, which includes muscle, bone, and water, body fat percentage is a more accurate measure of health risk. The NHS recommends using both BMI and waist circumference to assess weight-related health, but understanding your actual fat mass in pounds can provide additional context for your weight management journey.
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 Body Fat in Pounds is Calculated
To calculate your body fat in pounds, you first need to know your body fat percentage — the proportion of your total weight that is fat tissue. This is typically measured using methods like bioelectrical impedance analysis (BIA), DEXA scans, or skinfold calipers. Once you have your body fat percentage, the calculation is straightforward: multiply your total weight in pounds by your body fat percentage, then divide by 100.
Example: If you weigh 154 lbs (70 kg) with 25% body fat: 154 × 0.25 = 38.5 lbs of body fat.
The NHS recommends assessing body composition using BMI as a screening tool, though BMI has limitations — it doesn't distinguish between muscle and fat. Our free BMI calculator provides a quick health screening starting point, and our weight converter helps you switch between kg and pounds easily for comparison with clinical guidelines.
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.
Healthy Body Fat Ranges for UK Adults
The American Council on Exercise provides widely-used reference ranges for body fat percentages. For women, 'acceptable' body fat is 25–31%, whilst for men it's 18–24%. Essential fat — the minimum needed for vital body functions — is 10–13% for women and 2–5% for men.
The NHS emphasises that healthy weight isn't just about a number on the scales. Using our free BMI calculator alongside waist circumference measurements gives a more complete picture of your health. If you're tracking weight loss, our progress tracker lets you log changes over time and see patterns beyond just pounds lost.
- 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's the difference between body weight and body fat in pounds?
Total body weight includes muscle, bone, organs, and water — everything. Body fat in pounds is only the weight of fat tissue. Two people at the same weight can have very different body fat levels depending on muscle mass. This is why BMI has limitations; it can't distinguish between a fit athlete and someone with excess fat.
How do I measure my body fat percentage accurately?
Professional methods include DEXA scans (most accurate, uses X-rays), bioelectrical impedance analysis (BIA scales), and skinfold calipers (requires training). Many gyms offer BIA testing. For a free home screening, use our BMI calculator and measure your waist circumference — the NHS recommends these as practical first-step health indicators.
Is body fat percentage more important than BMI for health assessment?
Both are useful. BMI is a quick screening tool — quick and free — but doesn't account for muscle mass. Body fat percentage is more specific but harder to measure accurately. The NHS recommends using BMI alongside waist circumference for a fuller picture. Try our free BMI calculator and waist measurement together.
Can I lose fat in pounds without losing total weight?
Yes. If you're strength training, you can build muscle whilst losing fat — your total weight may stay the same but your body fat in pounds decreases. This is why scales alone are misleading. Track progress using our free progress tracker alongside measurements and how clothes fit.
What body fat percentage should I aim for if I'm overweight?
The NHS recommends starting with a BMI in the healthy range (18.5–24.9) rather than targeting a specific body fat percentage first. Body fat goals vary widely based on genetics, age, and fitness level. Use our free BMI calculator to find your target weight range, then focus on sustainable diet and activity changes alongside professional guidance if needed.
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.