What Is the NHS Healthy Weight Calculator?
Our free NHS healthy weight calculator is designed to answer the most common health question asked by UK adults: "What should I weigh?" By entering your height, the calculator works backwards from the NHS healthy BMI range (18.5–24.9) to give you your precise healthy weight range in kilograms and stones, along with your ideal weight (the midpoint of the healthy range) and personalised NHS guidance for 2026.
Unlike a standard BMI calculator, which tells you your current BMI category, our healthy weight calculator NHS tells you your target — the specific weight range you should be aiming for. If you enter your current weight too, the calculator will tell you exactly how much you need to lose or gain, and how long this will take at the NHS-recommended safe rate of 0.5–1 kg per week.
✅ Key 2026 NHS definition: A healthy weight is one that corresponds to a BMI between 18.5 and 24.9 for most UK adults. This range is the same used by NHS GPs and is the foundation of NHS weight management programmes across England. Use the calculator above to find your exact healthy weight range for your height.
What Should I Weigh? NHS Healthy Weight by Height 2026
The question "what should I weigh UK NHS?" is one of the most searched health questions in the UK. The answer depends entirely on your height — and the NHS uses BMI to set the boundaries. Here is a reference table showing NHS healthy weight ranges for common heights:
| Height | Minimum Healthy | Ideal Weight | Maximum Healthy |
|---|---|---|---|
| 5'0" (152 cm) | 42.7 kg (6 st 10 lb) | 50.1 kg (7 st 13 lb) | 57.4 kg (9 st 1 lb) |
| 5'2" (157 cm) | 45.6 kg (7 st 3 lb) | 53.5 kg (8 st 6 lb) | 61.4 kg (9 st 9 lb) |
| 5'4" (163 cm) | 49.1 kg (7 st 10 lb) | 57.6 kg (9 st 1 lb) | 66.1 kg (10 st 6 lb) |
| 5'6" (168 cm) | 52.2 kg (8 st 3 lb) | 61.2 kg (9 st 9 lb) | 70.3 kg (11 st 1 lb) |
| 5'8" (173 cm) | 55.3 kg (8 st 10 lb) | 64.9 kg (10 st 3 lb) | 74.5 kg (11 st 10 lb) |
| 5'10" (178 cm) | 58.6 kg (9 st 3 lb) | 68.7 kg (10 st 11 lb) | 78.9 kg (12 st 6 lb) |
| 6'0" (183 cm) | 62.0 kg (9 st 11 lb) | 72.8 kg (11 st 6 lb) | 83.5 kg (13 st 2 lb) |
| 6'2" (188 cm) | 65.5 kg (10 st 4 lb) | 76.9 kg (12 st 1 lb) | 88.3 kg (13 st 13 lb) |
For a precise healthy weight range for your exact height — including in both metric and imperial — use the calculator above. For the mathematical background on how BMI is calculated, see our guide on the BMI formula explained with examples and our step-by-step walkthrough on how to calculate BMI step by step. For a deeper comparison of calculation methods, see BMI equation vs BMI calculator — what's the difference.
Ideal Weight NHS — How Is It Defined?
The NHS does not define a single "ideal weight" for a given height — instead, it recognises a healthy weight range corresponding to BMI 18.5–24.9. Any weight within this range is considered healthy by NHS guidelines in 2026.
When people refer to ideal weight NHS, they typically mean one of three things:
- Lower healthy weight: The minimum weight for a healthy BMI (BMI 18.5) — useful for those who are underweight and want to know their target
- Upper healthy weight: The maximum weight for a healthy BMI (BMI 24.9) — the threshold above which the NHS classifies weight as overweight
- Midpoint ideal weight: The weight corresponding to BMI 21.7 — the midpoint of the healthy range, often used as a practical target weight
For a dedicated ideal weight calculation, use our Ideal Weight Calculator UK — which provides your healthy weight range alongside your ideal weight for your height. To see how your body shape relates to your BMI category, use our Visual BMI Calculator.
What Should I Weigh? — How the NHS Weight Calculator Works
Our NHS weight calculator uses a reverse-BMI approach: instead of calculating your BMI from your current weight, it calculates your target weight from your BMI thresholds. The mathematics are straightforward:
📐 Healthy weight formula:
Minimum healthy weight = 18.5 × Height (m)²
Maximum healthy weight = 24.9 × Height (m)²
Ideal weight (midpoint) = 21.7 × Height (m)²
Example for 5'7" (170 cm / 1.70 m):
Min: 18.5 × (1.70)² = 18.5 × 2.89 = 53.5 kg
Max: 24.9 × (1.70)² = 24.9 × 2.89 = 71.9 kg
Ideal: 21.7 × (1.70)² = 21.7 × 2.89 = 62.7 kg
If you enter your current weight, the calculator also tells you how far you are from the healthy range and how long it will take to reach it at the NHS-recommended safe rate of weight loss or gain. For a full explanation of the safe weight loss rate, see our guide on the safe rate of weight loss per week and how much weight you can lose per week safely.
NHS Healthy Weight — Important Limitations to Know
The NHS uses BMI as its primary healthy weight reference tool for adults, but openly acknowledges that BMI has limitations. The following groups may need to interpret their healthy weight range differently:
Athletes and Muscular Adults
High muscle mass can push BMI into the "overweight" range despite very low body fat. For very muscular individuals, the NHS recommends assessing waist circumference and body fat percentage alongside BMI. The NHS healthy weight calculator may overestimate ideal weight for this group.
South Asian, Chinese, and Other Ethnic Groups
The NHS applies lower BMI thresholds for South Asian and Chinese adults: overweight from BMI 23 and obese from BMI 27.5 (compared to 25 and 30 for the general population). This is because these ethnic groups face higher metabolic risk at lower BMI values. If this applies to you, your upper healthy weight threshold is lower than shown by the standard calculator.
Older Adults (65+)
For adults aged 65 and over, the NHS sometimes accepts a slightly higher BMI (up to 27) as healthy, because older adults with lower BMI may have more risk from frailty and muscle loss than from excess fat. Speak to your GP for age-appropriate weight guidance.
Pregnant Women
BMI-based healthy weight targets do not apply during pregnancy due to expected weight gain from the baby, placenta, and amniotic fluid. Use your pre-pregnancy BMI as a reference point. After pregnancy, use our calculator to set a gradual, realistic target. For pregnancy tools, see our Pregnancy Due Date Calculator NHS.
How to Reach Your NHS Healthy Weight — 2026 Guide
Once you know your healthy weight target, the next step is understanding how to reach it safely. The NHS recommends the same approach in 2026 as it has consistently endorsed: gradual, sustainable change through diet and physical activity — not crash dieting or extreme restriction.
Safe Rate of Weight Loss
Both NHS and CDC guidelines recommend 0.5 to 1 kg per week as the safe rate of weight loss. This requires a daily calorie deficit of 500–1,000 kcal. For a full explanation of why this rate matters and how to achieve it, see our guides: the 0.5–1 kg weight loss rule explained and our comparison of NHS vs CDC weight loss guidelines explained. To calculate your personal daily calorie target, use our Calorie Deficit Calculator NHS.
Diet — NHS Eatwell Guide Principles
The NHS Eatwell Guide recommends: half your plate as fruit and vegetables; a quarter as wholegrains and starchy carbohydrates; a quarter as lean protein. Reduce ultra-processed foods, sugary drinks, and excess saturated fat. Limit salt to 6g per day. Adequate protein (1.2–1.6 g/kg body weight) is particularly important to preserve muscle mass during weight loss.
Exercise — 150 Minutes Per Week
The NHS recommends at least 150 minutes of moderate-intensity aerobic activity per week for adults. In 2026, NHS services increasingly combine this with resistance training to preserve lean muscle during weight loss. Even brisk walking for 30 minutes five times per week meets the NHS exercise guideline and contributes to your calorie deficit.
All Our NHS Health Tools — Your Complete Toolkit
Our NHS healthy weight calculator is one of many free NHS-aligned health tools on this website. Here is your complete toolkit for health management in 2026:
📚 Also read: Our health blog covers safe rate of weight loss per week, how much weight you can lose per week safely, NHS vs CDC weight loss guidelines explained, the 0.5–1 kg rule explained, and how to calculate BMI step by step. All free, NHS-aligned, and updated for 2026.
Frequently Asked Questions
According to NHS 2026 guidelines, a healthy weight is one that corresponds to a BMI between 18.5 and 24.9 for most adults. The NHS also recommends a waist circumference below 80 cm for women and below 94 cm for men. Use our calculator above to find your precise NHS healthy weight range for your height. For the BMI calculation method, see BMI formula explained with examples.
Your healthy weight range depends on your height. The NHS calculates it using BMI (BMI 18.5–24.9). For example, for someone who is 5'7" (170 cm), the NHS healthy weight range is approximately 53.5 to 71.9 kg (8 st 6 lb to 11 st 4 lb). Use our NHS healthy weight calculator above for your exact range. For a visual representation, use our Visual BMI Calculator.
The calculator uses a reverse-BMI approach: it takes your height and calculates the weight range corresponding to BMI 18.5 (minimum healthy) to BMI 24.9 (maximum healthy) using the formula: Weight = BMI × Height (m)². If you enter your current weight, it also calculates your current BMI, how far you are from the healthy range, and how long it will take at the NHS-recommended rate of 0.5–1 kg per week.
NHS ideal weight typically refers to the midpoint of the healthy BMI range — corresponding to a BMI of approximately 21.7. This represents the centre of the NHS healthy weight range (18.5–24.9). However, any weight within the healthy range is medically appropriate — you do not need to aim for a specific single number. Use our Ideal Weight Calculator UK for more detail.
The NHS recommends losing 0.5 to 1 kg (1 to 2 lbs) per week as the safe rate of weight loss. This is achieved through a daily calorie deficit of 500–1,000 kcal via a balanced diet and at least 150 minutes of moderate physical activity per week. Use our Calorie Deficit Calculator NHS to find your daily calorie target. See also: the 0.5–1 kg rule explained.
No — this calculator is for adults aged 18+. Adult BMI thresholds (18.5–24.9) do not apply to children, whose BMI must be interpreted using age- and sex-specific NHS centile charts. For children aged 2–18, use our Child BMI Calculator NHS. For full growth tracking, use our Child Growth Chart Calculator UK and Percentile Calculator UK.