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
What Is The Average BMI For A Woman?
The average BMI for UK adult women is approximately 27.4, which falls into the overweight category according to NHS guidelines. However, average does not mean healthy — the NHS recommends a healthy BMI range of 18.5 to 24.9 for most women. Your individual healthy weight depends on your height, age, and overall health. This guide explains NHS BMI categories, how to calculate your personal BMI, and why average figures matter less than your own health context. Use our free BMI calculator above to check your personal BMI instantly and see where you fall on the NHS scale.
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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.
Understanding BMI Categories And UK Healthy Ranges
The NHS divides BMI into clear categories that help identify health risk levels. A healthy BMI for women ranges from 18.5 to 24.9 — this is the target range associated with the lowest risk of weight-related health conditions. An overweight BMI ranges from 25 to 29.9, while obese BMI starts at 30 and above. The average BMI of 27.4 for UK women reflects that many fall into the overweight category. Using the BMI formula (weight in kg ÷ height in metres squared), you can calculate where you personally fit. For women of South Asian, Chinese, Black African, or Black Caribbean heritage, the NHS recommends slightly lower thresholds — healthy BMI starts at 18.5 and overweight begins at 23. This is because these groups face higher health risks at lower BMI levels. Calculate your personal BMI using the calculator on this page to see your individual category and healthy weight range for your height.
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.
BMI Limitations And What Else Matters
While BMI is a useful screening tool, it has important limitations you should understand. BMI does not distinguish between muscle and fat — athletes may have high BMI but low body fat. It also ignores where fat is stored; abdominal (belly) fat carries greater health risk than fat elsewhere. The overweight BMI threshold doesn't account for individual age, bone density, or fitness level. For a more complete health picture, your GP may also assess your waist circumference (over 88cm for women indicates increased health risk) and overall fitness. Rather than focusing solely on average figures, discuss your personal healthy weight range with your GP, who can consider your medical history and individual circumstances. The goal is sustainable health, not matching an average.
- 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.
Is an average BMI of 27.4 for women healthy?
No — the average BMI of 27.4 falls into the overweight category. The NHS healthy range is 18.5–24.9. Average does not mean healthy; many UK women are above their healthy weight. If your BMI is higher than healthy for your height, modest weight loss can improve health even without reaching an "ideal" number.
How do I calculate my BMI as a woman?
Divide your weight in kilograms by your height in metres squared. For example, a woman weighing 70kg who is 1.65m tall: 70 ÷ (1.65 × 1.65) = BMI of 25.7. Use our free BMI calculator above to work this out instantly for your own measurements.
What's the healthy weight range for a woman who is 5ft 5in (165cm)?
At 165cm, the healthy BMI range of 18.5–24.9 equals approximately 50–67kg (7st 12lbs to 10st 7lbs). Your GP can advise your personal healthy range based on your health, fitness, and medical history. Use the weight converter on this page to switch between kg and stone.
Do ethnic background and BMI thresholds matter?
Yes. The NHS recommends lower BMI thresholds for South Asian, Chinese, Black African, and Black Caribbean women — healthy BMI starts at 18.5 but overweight begins at 23 (not 25). This reflects higher cardiovascular and diabetes risk in these groups at lower BMI levels.
What should I do if my BMI is higher than the healthy range?
Speak to your GP for personalised advice. Even a 5–clinically studied weight loss can improve health. Your GP may discuss nutrition, physical activity, and whether any support or treatment might help. Track your progress with our free progress tracker tool.
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.