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
NHS Weight Loss App and Weight Management Support in the UK
The NHS offers several weight loss support options across the UK, though there isn't a single "NHS weight loss app" available to everyone. Weight management support varies significantly by region, from digital programmes and apps to specialist services and prescription weight loss medication. Your GP can help you access appropriate weight management UK support based on your circumstances. Understanding what's available and how to access it is the first step towards sustainable weight loss.
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.
What Weight Loss Support Does the NHS Offer?
The NHS provides weight management support across four tiers, depending on your needs and local availability:
- Tier 1: Self-help resources, digital tools, and community weight loss programmes (often free or low-cost)
- Tier 2: Primary care interventions through your GP surgery, including behaviour change support and structured weight loss programmes
- Tier 3: Specialist multidisciplinary weight management services — where prescription weight loss medication may be prescribed
- Tier 4: Specialist bariatric surgery services for severe obesity with significant health complications
Access varies by region. Your local Integrated Care Board (ICB) determines which services are funded and available. Use our free BMI calculator above to check your starting point, then discuss weight management options with your GP to see what tier of support is appropriate for you.
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 Medication and the NHS
The NHS has approved prescription weight loss medication including GLP-1 injections and other medications for eligible adults. However, prescription weight loss medication is typically only available through tier 3 specialist services, not directly from your GP. Eligibility usually requires a BMI of 30 or above, or 27 or above with weight-related health conditions such as type 2 diabetes or high blood pressure. Waiting times for NHS specialist services vary considerably by region — in some areas, waits can be several months or longer. If you're interested in prescription weight loss support, discuss this with your GP to understand local availability and waiting lists. Our GLP-1 weight loss calculator can help you estimate potential results if you do become eligible.
- 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 there an official NHS weight loss app available to download?
There is no single official "NHS weight loss app" available to all UK residents. However, some NHS trusts and local services offer digital weight management programmes or apps through their weight management services. Your GP can advise whether your local NHS area offers digital support tools. Private weight loss apps like MyFitnessPal are also widely used alongside NHS support.
How do I access NHS weight loss support?
Start by contacting your GP. They can assess your weight, health conditions, and local services available. Your GP will refer you to appropriate support — which might be tier 2 primary care programmes, digital tools, or a tier 3 specialist weight management service if you're eligible for prescription medication or intensive support.
What's the difference between lose weight UK private apps and NHS weight loss support?
NHS services are free and tailored to your individual health needs, but availability varies by region and waiting lists can be long. Private apps and services are immediately accessible but involve costs. Many people use a combination — NHS support for clinical guidance and private tools for tracking and motivation.
How long is the NHS waiting list for specialist weight management services?
Waiting times vary significantly by region and local demand. Some areas have waits of several weeks, others several months or longer. Your GP can tell you the current waiting time for tier 3 services in your area when you request a referral.
Can I get prescription weight loss medication like Mounjaro or Wegovy through the NHS?
Yes, prescription weight loss medication is available through NHS tier 3 specialist weight management services for eligible adults. However, this typically requires referral from your GP, clinical assessment by specialists, and meeting eligibility criteria. Availability and waiting times vary significantly by region.
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.