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 57.9 Kg In Stone And Pounds?
57.9 kg is equivalent to 9 stone 1.3 pounds (or 9 stone 1 lb). However, whether this weight is healthy depends entirely on your height. Using our free BMI calculator above, you can find your exact BMI by entering your height. The same weight gives a very different BMI for someone 5ft 2in compared to someone 5ft 10in, which is why height is crucial when assessing weight health according to NHS guidelines.
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.
BMI For 57.9 Kg At Different Heights
57.9 kg to stone conversion: 9 stone 1.3 pounds exactly. To convert kilograms to stone, divide by 6.35. Your BMI depends on your height — the same weight in kilograms produces very different health categories for different people.
- At 5ft 2in (157 cm): BMI = 23.5 (healthy weight)
- At 5ft 4in (163 cm): BMI = 21.8 (healthy weight)
- At 5ft 6in (168 cm): BMI = 20.5 (healthy weight)
- At 5ft 8in (173 cm): BMI = 19.4 (healthy weight)
- At 5ft 10in (178 cm): BMI = 18.2 (underweight)
- At 6ft 0in (183 cm): BMI = 17.3 (underweight)
For a kilogram to stone conversion at any height, use our free weight converter on this page to switch between metric and imperial measurements instantly.
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.
NHS BMI Categories And Limitations
According to NHS guidelines, a healthy BMI is 18.5 to 24.9 for most UK adults. At 57.9 kg, you fall into the healthy range if you're between 5ft 2in and 5ft 8in tall. If you're taller, your BMI may be lower — which is still healthy.
Important: BMI does not account for muscle mass, bone density, or where fat is stored. An athletic person with high muscle may have a high BMI but low body fat. For this reason, your GP may also consider waist circumference (healthy is under 80 cm for women, under 94 cm for men) alongside BMI for a complete health picture.
- 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 convert 57.9 kg to stone and pounds?
Divide 57.9 by 6.35 to get stone (9.12 stone), then multiply the decimal (0.12) by 14 to get pounds (1.7 lbs). Result: 9 stone 1.7 pounds. Use the weight converter on this page for instant conversions between kg, stone, and lbs.
Is 57.9 kg a healthy weight?
It depends on your height. At 57.9 kg, your BMI is healthy (18.5–24.9) if you're between 5ft 2in and 5ft 8in tall. Use our free BMI calculator above to find your exact BMI by entering your height for personalised guidance.
What is my BMI at 57.9 kg if I'm 5ft 6in tall?
At 5ft 6in (168 cm), a weight of 57.9 kg gives a BMI of 20.5, which falls in the healthy weight range according to NHS guidelines (18.5–24.9). This suggests good weight health for your height.
What are the NHS BMI categories?
NHS categories are: underweight (below 18.5), healthy weight (18.5–24.9), overweight (25.0–29.9), obese (30.0–34.9), and severely obese (40.0+). For South Asian, Chinese, Black African, or Black Caribbean adults, thresholds are lower due to higher health risks at the same BMI.
Does BMI tell the whole health story?
No. BMI doesn't distinguish between muscle and fat, and doesn't show where fat is stored. Waist circumference (under 80 cm for women, 94 cm for men) is also important. Your GP can assess your overall health using BMI alongside other factors.
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.