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 100 Lbs in Stone and Kilograms?
100 pounds is equal to 7 stone 2 lbs (or 7.16 stone) and 45.4 kilograms. In the UK, we typically express body weight using stone and pounds, so understanding this conversion is useful when checking your NHS health guidelines or using fitness trackers that default to metric. Use our free weight converter above to switch between kg, stone, and lbs instantly for any weight value.
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 Convert 100 Lbs to Stone
Converting pounds to stone is straightforward using the standard UK conversion formula. Since 1 stone equals exactly 14 pounds, you divide the total pounds by 14 to find the stone value. For 100 lbs: 100 ÷ 14 = 7 stone with 2 pounds remaining. To convert to kilograms, multiply pounds by 0.453592, giving 45.4 kg. The reverse calculation works the same way—multiply stone by 6.35029 to get kilograms, or multiply stone by 14 then add any remaining pounds to get total pounds. These conversions are essential when interpreting NHS health guidance, BMI charts, or personal weight loss targets, as different healthcare resources use different measurements. Our free BMI calculator can instantly show you where 100 lbs falls within the 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.
Is 100 Lbs a Healthy Weight for an Adult?
Whether 100 lbs is a healthy weight depends entirely on your height and age. For an adult female of average UK height (5ft 4in or 163cm), 100 lbs gives a BMI of approximately 17.2, which falls within the healthy weight range of 18.5–24.9. For a taller adult, 100 lbs would be underweight; for a shorter adult, it could be overweight. The NHS recommends calculating your personal BMI and consulting your GP if you have concerns about whether your weight is healthy for your individual circumstances. Use our free BMI calculator above to check your specific BMI based on your height—this gives you a clearer picture of where you stand within NHS healthy weight guidance.
- 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 is 100 lbs in stone?
100 lbs equals 7 stone 2 lbs (7.16 stone). Since 1 stone = 14 lbs exactly, divide 100 by 14 to get 7 with a remainder of 2 pounds.
What is 100 lbs in kilograms?
100 lbs is approximately 45.4 kg. Multiply pounds by 0.453592 to convert to kilograms. This metric measurement is used by the NHS and most UK healthcare providers.
Is 100 lbs a healthy weight?
It depends on your height. For someone 5ft 4in tall, 100 lbs gives a BMI of 17.2 (healthy). For taller adults, it may be underweight; for shorter adults, it could be overweight. Use the BMI calculator on this page to check your personal BMI.
How do I convert between stone and kilograms?
To convert stone to kg, multiply by 6.35029. To convert kg to stone, divide by 6.35029. For 7 stone 2 lbs: multiply 7.14 stone × 6.35029 = 45.4 kg. Try our weight converter for any weight value.
What does the NHS say about healthy weight?
The NHS recommends a BMI between 18.5 and 24.9 for most adults. For South Asian, Chinese, Black African, or Black Caribbean adults, the threshold is 18.5–22.9. Your GP can advise whether your weight is healthy based on your individual health profile.
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.