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
Best Weight Loss Apps for UK Users
Finding the right weight loss app can make a real difference to your weight management journey. Whether you're tracking calories, monitoring your BMI, or planning meals, the best apps combine ease of use with practical features that support sustainable weight loss. This guide covers the top-rated apps available to UK users, what features matter most, and how to choose one that fits your lifestyle.
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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.
Top Weight Loss Apps Available in the UK
The most popular weight loss apps in the UK fall into several categories:
- Calorie tracking apps — MyFitnessPal and Cronometer allow you to log meals, track macronutrients, and see your daily calorie intake against your targets. These work best alongside a reduced-calorie diet plan.
- Fitness and lifestyle apps — Strava and Strong focus on exercise tracking, helping you increase physical activity alongside dietary changes.
- Meal planning apps — Apps like Mealime and PlateJoy provide recipe suggestions and shopping lists aligned to your weight loss goals.
- Comprehensive weight management apps — MyNetDiary and Lose It combine food logging, exercise tracking, and social support features.
The NHS also recommends using evidence-based apps that support behavioural change, not just counting. Many apps are free to start with premium features available.
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.
Features to Look For in a Weight Loss App
The best weight loss apps for UK users should include: accurate UK food databases (including supermarket branded items and restaurant chains), flexible calorie targets that adjust as you progress, progress tracking that shows trends over weeks not just days, and barcode scanning for quick food entry. Look for apps that integrate with fitness trackers and smartwatches. Consider using our free progress tracker alongside an app — logging your weight weekly helps you spot genuine trends and stay motivated. Many apps also include community features, which some users find motivating, while others prefer privacy.
- 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.
Can weight loss apps replace a prescribed weight loss medication?
No. Apps are tools to support lifestyle changes — diet and exercise. If your GP has prescribed medication like Mounjaro or Wegovy for weight management uk, an app can help you track progress alongside the medication, not instead of it. Apps work best combined with other weight loss approaches.
Are free weight loss apps as good as paid versions?
Many free apps have comprehensive features. The difference is usually in advanced analytics, ad-free experience, or premium meal plans. Start with a free version — MyFitnessPal, Lose It, and Cronometer all have solid free tiers. Upgrade only if you need specific features.
Which UK weight loss app integrates best with NHS services?
The NHS-approved Diabetes Prevention Programme app (NHS DPP) is designed specifically for UK users and is free. Some NHS trusts also recommend Headspace for stress management alongside weight loss. Check with your local NHS weight management service for their recommendations.
How do I know if a weight loss app is evidence-based?
Look for apps developed by healthcare professionals or companies that reference clinical trials. Check if they're mentioned on NHS websites or NICE guidance. Avoid apps making clinically studied weight loss claims — evidence-based apps use conditional language like "may help" and emphasise sustainable, gradual weight loss.
Should I use an app if I'm taking prescription weight loss medication?
Yes. Apps help you track whether you're maintaining a reduced-calorie diet and increasing activity alongside medication like Mounjaro. Use your app to log meals and exercise, then use our free GLP-1 weight loss calculator to estimate projected outcomes and monitor progress over time.
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.