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
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Top Free Weight Loss Apps for UK Users
Managing your weight effectively often starts with the right tools. Free weight loss apps can help you track calories, monitor your progress, and stay motivated as part of a structured weight management UK approach. Whether you're using lifestyle changes alone or working with your GP on prescription weight loss medication, digital apps complement your efforts by providing real-time feedback and accountability. This guide covers the best free options available to UK users, plus how apps fit into the broader picture of 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.
The Best Free Weight Loss Apps Available in the UK
MyFitnessPal remains one of the most popular free weight loss apps globally, with a UK-focused version. It includes a food database of over 11 million items, calorie tracking, exercise logging, and barcode scanning. The free version covers essential features, though premium offers meal planning and more detailed analytics.
Lose It! is another strong option for UK users, offering a straightforward calorie counter with a colour-coded system that makes it intuitive. It integrates with fitness trackers and provides weekly weigh-in tracking.
Yazio combines calorie counting with meal planning and recipe suggestions aligned to UK portion sizes. It's particularly useful if you want guided meal structure alongside tracking.
Cronometer focuses on micronutrient tracking alongside calories — useful if you're concerned about nutritional balance during weight loss.
For those interested in structured approaches, the NHS Weight Loss Plan app offers free support based on NHS guidelines, including behaviour change techniques and weekly tips tailored to UK adults.
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.
How to Choose the Right App for Your Weight Loss Goals
The best app is the one you'll actually use consistently. Consider whether you prefer simple calorie counting or more detailed nutritional tracking. Some users benefit from visual progress tracking and motivational features, whilst others prefer minimalist interfaces.
Free apps work best alongside other weight management strategies. If you're following NHS weight loss guidance, an app can track your 500-calorie daily deficit. If you're exploring prescription weight loss medication through your GP, apps help monitor whether you're meeting recommended healthy eating and physical activity targets. Use our free BMI calculator to establish your baseline, then track changes over time with an app — many apps integrate with fitness trackers for seamless data syncing.
Remember that apps are tools to support you, not replacements for professional advice. Your GP remains your first point of contact for personalised weight management guidance.
- 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.
Are free weight loss apps as good as paid versions?
Free versions of major apps (MyFitnessPal, Lose It!) include core features most users need — calorie counting, food databases, progress tracking. Premium versions add meal planning, detailed analytics, and ad removal. For most people starting their weight loss journey, free versions are sufficient.
Can I use a weight loss app alongside prescription weight loss medication?
Yes. Apps help you track whether you're meeting recommended reduced-calorie diet and physical activity targets whilst taking medications like Mounjaro or Wegovy. Your prescriber may recommend using an app to monitor your progress alongside check-ins.
Which app is best for NHS weight loss guidance?
The NHS Weight Loss Plan app is specifically designed around NHS recommendations. MyFitnessPal and Lose It! also work well with NHS targets — they allow you to set a 500-calorie daily deficit, which aligns with NHS guidance for safe weight loss.
Do weight loss apps work without exercise tracking?
Yes. Calorie deficit drives weight loss, so apps focused only on food tracking are effective. However, combining food tracking with activity logging (walking, gym, cycling) gives a complete picture and supports better long-term habits.
Can I use an app if I don't want to count calories?
Some apps use simplified systems (Lose It!'s colour-coding, portion-size guides) that don't require detailed calorie counting. However, most free apps rely on calorie awareness as their core feature — if calorie counting isn't for you, a behaviour change programme or support from your GP may be a better fit.
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.