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 Target Calculator — How to Set Realistic Goals
Setting a realistic weight loss target is one of the most important steps in any weight management journey. The NHS recommends losing weight at a safe, sustainable rate of 0.5 to 1 kg per week, which helps protect muscle mass and makes results more likely to stick. Our free BMI calculator and GLP-1 weight loss calculator can help you understand where you are now and what a healthy target weight looks like for your height. This guide covers how to calculate your target, understand healthy weight ranges, and track progress effectively using evidence-based methods.
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 Calculate Your Healthy Target Weight
Your healthy target weight depends on your height and sits within a BMI range of 18.5 to 24.9 according to NHS guidelines. To calculate your healthy weight range, use this formula: multiply your height in metres by itself, then multiply by 18.5 (for the lower bound) and 24.9 (for the upper bound).
For example, if you're 1.73m tall (5ft 8in), your healthy weight range is approximately 55 to 75 kg (8st 8lbs to 11st 10lbs). If you're of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends a slightly lower target range (BMI 18.5–22.9), which may mean a lower upper target weight. Use our free weight converter to see your target in stone and pounds instantly. Your GP can provide personalised guidance on what's realistic for your individual circumstances, medical history, and fitness level.
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.
Realistic Weight Loss Targets and Timescales
A safe, sustainable weight loss of 0.5 to 1 kg per week means losing roughly 2 to 4 kg per month. To lose 10 kg, you'd typically need 10–20 weeks at this rate. This pace is achievable through a calorie deficit of around 500 kcal per day, combined with increased physical activity. Faster weight loss is possible with prescription weight loss medication like GLP-1 injections (Mounjaro or Wegovy), which may support additional weight reduction alongside a reduced-calorie diet and exercise. Our free progress tracker helps you log your weight regularly and visualise your progress towards your target. Remember that progress isn't always linear—plateaus are normal and don't mean you're failing.
- 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.
How do I calculate my healthy target weight?
Multiply your height in metres by itself, then multiply by 18.5 for the lower healthy bound and 24.9 for the upper bound. For example, at 1.75m tall, your healthy range is 56–76 kg. Use our free BMI calculator to check your current BMI instantly.
What's a realistic weight loss rate in the UK?
The NHS recommends 0.5 to 1 kg per week, achieved through a calorie deficit of around 500 kcal daily. This typically means losing 2–4 kg monthly. Faster loss may be possible with prescription weight loss medication, though individual results vary.
Should I use a different target weight if I'm of South Asian or Black heritage?
Yes. The NHS recommends lower BMI thresholds for South Asian, Chinese, Black African, and Black Caribbean adults due to higher health risks at lower weights. Aim for a BMI of 18.5–22.9 rather than 18.5–24.9. Discuss your personal target with your GP.
How can weight loss injections help me reach my target?
GLP-1 medications like Wegovy and Mounjaro are prescription-only weight management tools licensed in the UK. Clinical trials showed they support additional weight loss alongside diet and exercise. Eligibility depends on BMI and health factors—your GP or a licensed prescriber can assess suitability.
How often should I weigh myself and adjust my target?
Weekly weigh-ins are reasonable; daily weighing can be demotivating due to natural fluctuations. Review your progress monthly. If you reach your initial target, you may set a new goal or focus on maintaining it. Our free progress tracker makes logging weight changes simple and motivating.
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.