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
Affordable Weight Loss in the UK — Your Options Explained
Weight loss doesn't have to be expensive, but understanding your options — from free NHS support to prescription medication — helps you find what fits your budget and health needs. Whether you're looking at lifestyle changes, NHS services, or weight loss medication, there are affordable pathways available across the UK. We'll break down the real costs and what you can actually access.
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.
Free and Low-Cost Weight Management in the UK
The NHS offers completely free weight management support through various tiers of care. Tier 1 includes self-help digital tools and community programmes — many available at no cost beyond your NHS contribution. The NHS Weight Loss Plan is free and accessible online, offering guidance on calorie reduction and behaviour change. Tier 2 provides GP-led support and structured behaviour change programmes, also free. Calculating your BMI weight loss baseline costs nothing — use our free BMI calculator above to establish where you're starting from. For many people, sustainable weight loss through diet and physical activity remains the most affordable option. A calorie deficit of around 500 kcal per day typically results in approximately 0.5 kg per week loss without any cost beyond your food choices.
- NHS Tier 1: Digital tools and community support — free
- NHS Weight Loss Plan: Online guidance — free
- GP consultations: Free through NHS
- Lifestyle changes: Only food cost differences
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.
Prescription Weight Loss — NHS vs. Private Cost
NHS weight loss medication is free at point of use if prescribed, but access is limited. You'll need referral to a specialist Tier 3 weight management service, and availability varies significantly by region with potential waiting lists of months or longer. Private weight loss injections uk cost approximately £129–£320 per month depending on dose and provider. GLP-1 weight loss medications like Wegovy (semaglutide) are prescription-only and require clinical assessment before dispensing. This assessment fee typically ranges from £20–£50. Many private providers offer payment plans to spread costs. The NHS approach requires patience but costs nothing; private routes offer faster access but involve upfront expense. Use our GLP-1 weight loss calculator to estimate potential results and plan your investment.
Prescription weight loss uk options include GLP-1 injections and other medications, all requiring a valid prescription from a UK-licensed prescriber. Before committing to cost, assess your eligibility: you need a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes, high blood pressure, or cardiovascular disease. Lower thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults. Track your progress using our free progress tracker to measure whether any investment is delivering results. Many people find that combining affordable lifestyle changes with structured support — whether NHS or private — offers the best value. Costs are meaningful but so are the health benefits: even 5–clinically studied weight loss significantly improves blood pressure, blood sugar control, and overall health.
- 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.
Is weight loss free on the NHS?
Yes, NHS weight management is free at point of use. You can access Tier 1 support (digital tools, community programmes) immediately, and your GP can refer you to Tier 2 or Tier 3 services for more intensive support. Prescription medications are also free if prescribed through NHS specialist services, though regional availability varies and waiting lists can be long.
How much does private weight loss medication cost in the UK?
Private GLP-1 weight loss injections typically cost £129–£320 per month depending on dose and provider. Clinical assessment fees range from £20–£50. Some providers offer payment plans. Costs are ongoing — you'll need repeated prescriptions. Always factor in the full treatment duration when budgeting.
What's the cheapest way to lose weight in the UK?
Lifestyle changes — reducing calories through diet and increasing physical activity — cost nothing beyond your food budget. A 500 kcal daily deficit typically results in 0.5 kg weekly loss. Free NHS support through the Weight Loss Plan and GP services provides structured guidance. Our free BMI calculator and progress tracker help you track results without expense.
Can I get weight loss injections free on the NHS?
Yes, if prescribed through an NHS specialist Tier 3 weight management service. Access requires GP referral, meeting eligibility criteria (BMI ≥30 or ≥27 with health conditions), and availability in your area. Waiting lists are often several months. Private prescription routes offer faster access but involve cost.
Is affordable weight loss medication available in the UK?
GLP-1 medications like Wegovy and Mounjaro are available privately at approximately £150–£300 per month. The NHS option is free but involves waiting. Both require prescription-only clinical assessment. Results vary — use our GLP-1 calculator to estimate potential outcomes before deciding whether the investment is right 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.