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
Weight Loss Planner: Plan Your UK Health Journey
A weight loss planner helps you set realistic goals, track progress, and stay motivated throughout your weight management journey. Whether you're looking to lose weight through lifestyle changes, prescription medication, or a combination of approaches, having a structured plan significantly improves your chances of success. The NHS recommends losing weight at a rate of 0.5 to 1 kg per week for sustainable, lasting results. Using our free progress tracker alongside practical planning tools can help you monitor your weight loss and maintain momentum towards your health goals.
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.
How to Create an Effective Weight Loss Plan
A successful weight loss plan combines realistic goal-setting, dietary changes, and physical activity. Start by calculating your current BMI using our free BMI calculator above — this helps establish your baseline health status and appropriate weight loss targets.
- Set SMART goals: Specific, Measurable, Achievable, Relevant, and Time-bound. For example, "support gradual weight management" rather than "lose weight"
- Create a calorie deficit: A deficit of approximately 500 kcal per day typically results in about 0.5 kg weight loss per week
- Plan meals: Focus on whole foods, adequate protein, and controlled portions. The Mediterranean diet has strong evidence for sustainable weight management
- Add physical activity: Aim for 150 minutes of moderate activity weekly, combined with strength training 2–3 times weekly
- Track progress: Use our free progress tracker to log weekly weigh-ins and identify patterns
Many people also benefit from prescription weight loss support. If your BMI is 30 or above, or 27 or above with weight-related health conditions, you may be eligible for GLP-1 weight loss medication through NHS specialist services or private prescribing.
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.
Weight Loss Medication: Supporting Your Plan
For eligible adults, prescription weight loss medications like GLP-1 injections can complement your planner by reducing appetite and supporting portion control. Wegovy (semaglutide) and Mounjaro (tirzepatide) are both licensed for weight management in the UK and typically help achieve 15–clinically studied weight loss when combined with dietary and lifestyle changes.
Our GLP-1 weight loss calculator can help you estimate potential outcomes at different doses. These medications are prescription-only and require clinical assessment — your GP or a licensed prescriber will determine whether they're suitable for you based on your individual health profile. Remember: medication works best alongside the structured planning, nutrition, and activity elements of your weight loss strategy.
- 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.
What's a realistic timeline for weight loss?
The NHS recommends losing 0.5 to 1 kg per week through lifestyle changes. This pace is sustainable and protects muscle mass. For example, losing 10 kg typically takes 10–20 weeks. GLP-1 medications may accelerate results in some people, but individual outcomes vary. Your progress tracker helps monitor your personal timeline.
How much should I eat daily to lose weight?
A typical calorie deficit for weight loss is 1,500–1,800 kcal daily for women and 1,800–2,200 kcal for men, though individual needs vary based on height, activity level, and current weight. A GP or registered dietitian can provide personalised guidance. Focus on whole foods, adequate protein, and vegetables to feel fuller longer.
Can I use a weight loss planner with GLP-1 medication?
Yes — in fact, GLP-1 medications work best alongside the structured planning, dietary changes, and physical activity you'd include in any weight loss planner. Medication supports appetite control while your plan ensures you're eating nutritious foods and staying active. Combine planning with our GLP-1 weight loss calculator for realistic projections.
What if I'm overweight but not obese — can I get weight loss medication?
Yes. If your BMI is 27–29.9 and you have at least one weight-related health condition (type 2 diabetes, high blood pressure, high cholesterol, sleep apnoea, or cardiovascular disease), you may be eligible for prescription weight loss treatment. Your GP or prescriber can assess whether you qualify based on your individual circumstances.
How do I track weight loss progress effectively?
Weigh yourself weekly at the same time of day, ideally using our free progress tracker to log results and identify trends. Also monitor other metrics: how clothes fit, energy levels, fitness improvements, and blood pressure. Weight fluctuates naturally due to water retention and muscle gain — the weekly trend matters more than daily variations. --- ```
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.