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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Understanding Body Scales for Weight Tracking
A body scale is a simple tool that measures your body weight, but understanding how to use it accurately is key to effective weight management. In the UK, most people track their weight in stone and pounds, and consistent weighing is an important part of NHS-recommended health monitoring. Your scale's accuracy depends on proper placement, calibration, and regular use. Whether you're managing your weight for general health or working towards a specific goal, knowing how to use your scale correctly helps you get reliable measurements that you can track over time.
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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 Use a Body Scale Accurately
Placement and calibration are critical for accurate readings. Place your scale on a hard, level floor — not carpet or uneven surfaces, which can skew measurements. Digital scales should be zeroed (calibrated to 0 kg) before each use. Weigh yourself at the same time each day, ideally in the morning before eating or drinking, as this minimises daily fluctuations from food and water intake. Wear the same light clothing or no clothes each time for consistency.
- Use a hard, flat surface (not carpet)
- Zero your scale before weighing
- Weigh at the same time daily (morning is best)
- Stand still for 5 seconds to let the reading stabilise
- Record your weight immediately
Digital scales are generally more accurate than mechanical models. If your scale shows wildly inconsistent results, check the battery (if digital) or have it professionally calibrated. Remember that weight naturally fluctuates by 1–2 kg daily due to hydration, food intake, and hormonal changes — focus on weekly or monthly trends rather than daily variations.
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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 Tracking and Health Context
Using your body scale as part of a broader health guide means connecting your weight measurements to your BMI and overall wellness. Our free BMI calculator above helps you understand what your weight means for your health in terms of NHS guidelines. Tracking your weight over time using our progress tracker allows you to see patterns and identify whether lifestyle changes are having a positive effect.
For UK adults, the NHS recommends weighing yourself once a week to avoid obsessing over daily fluctuations. If you're working on weight management — whether through dietary changes, increased physical activity, or as part of a supervised weight loss plan — consistent scale measurements combined with body measurements (like waist circumference) give you a fuller picture of your health progress.
- 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 often should I weigh myself?
The NHS recommends weighing yourself once per week at the same time of day, ideally in the morning. Daily weighing can be discouraging due to normal water and food weight fluctuations. Weekly or monthly trends are more meaningful than daily changes.
Why do scales give different readings?
Scales can vary due to placement on uneven surfaces, poor calibration, battery issues (digital scales), or user technique. Always place your scale on a hard floor, zero it before use, and stand still while measuring. Different scales may also have slight calibration differences.
What's the difference between weight and BMI?
Weight is just a number — it doesn't account for muscle, bone density, or fat distribution. BMI combines your weight with your height to assess health risk. Use our free BMI calculator on this page to see how your weight translates to health guidance according to NHS standards.
Can I use a body scale to track weight loss progress?
Yes, but combine scale readings with other measurements like waist circumference and how your clothes fit. A scale measures total weight (including muscle, water, and fat), so it's most useful when tracked weekly over several months alongside lifestyle changes.
Should I use a smart scale or a regular digital scale?
Both work for basic weight tracking. Smart scales that sync to apps can help you track progress over time, but they're not essential. A standard digital scale is accurate enough if used consistently and placed on a hard, level surface. Choose whichever method you'll use regularly.
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.