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
How Much Weight Have I Lost? Calculate Your Progress
To work out how much weight you've lost, simply subtract your current weight from your starting weight. If you started at 95kg and now weigh 85kg, you've lost 10kg (1st 8lbs). Tracking your progress is motivating and important for understanding your health journey. This guide helps you calculate your weight loss, understand what a healthy weight range looks like for your height according to NHS guidelines, and keep perspective on your progress.
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.
Healthy Weight Ranges by Height (UK)
Your ideal weight depends entirely on your height, not just a number on the scales. According to NHS guidelines, a healthy weight range corresponds to a BMI of 18.5–24.9. Here's what a healthy weight for your height looks like across common UK heights:
- 5ft 2in (158cm): 47–63kg (7st 6lbs to 9st 13lbs)
- 5ft 4in (163cm): 50–68kg (7st 12lbs to 10st 10lbs)
- 5ft 6in (168cm): 54–74kg (8st 7lbs to 11st 9lbs)
- 5ft 8in (173cm): 58–79kg (9st 1lbs to 12st 6lbs)
- 5ft 10in (178cm): 62–85kg (9st 10lbs to 13st 5lbs)
- 6ft 0in (183cm): 67–91kg (10st 7lbs to 14st 4lbs)
Use our free BMI calculator above to find your personal healthy weight range instantly based on your height. Your weight calculator UK tool shows exactly where you fall within the NHS healthy range.
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.
Factors That Affect Your Ideal Weight
Your healthy weight range isn't one fixed number — it's a zone that varies based on your individual circumstances. Muscle weighs more than fat, so athletic people may fall at the higher end of the healthy range. Bone frame size, age, and genetics all influence what's truly healthy for you personally. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, NHS healthy weight thresholds are slightly lower because these groups have higher health risks at the same BMI. Your GP can discuss what weight is right for you, considering your complete health picture, not just the scales.
- 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.
How do I calculate how much weight I've lost?
Subtract your current weight from your starting weight. If you started at 100kg and now weigh 88kg, you've lost 12kg (1st 11lbs). For percentage loss: divide weight lost by starting weight and multiply by 100. This shows progress relative to where you began.
What is a healthy weight for my height?
A healthy weight range corresponds to a BMI of 18.5–24.9 according to NHS guidelines. Your specific healthy weight depends on your exact height. Use our free BMI calculator on this page to find your personal healthy weight range in both kg and stone.
Is there one "ideal weight" I should aim for?
No. Your ideal weight is a range, not a single number. Within the healthy BMI range for your height, where you fall depends on muscle mass, frame size, age, and genetics. Aim for the healthy range rather than one specific weight.
Why do different heights have different healthy weights?
Because BMI accounts for both weight and height together. The same weight looks very different on someone 5ft 2in versus 6ft tall. Taller people have more body surface area, so a higher weight can still be healthy.
How can I track my weight loss progress?
Use our free progress tracker on MyWeightCheck to log your weight regularly and visualise your journey over weeks and months. Tracking helps you stay motivated and shows whether you're losing weight at a healthy, sustainable rate of 0.5–1kg per week.
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.