BMI 170 cm / 45 kg

BMI US Metric BMI UK Calories
kg

Your BMI position: 15.6 — Severely Underweight (WHO)

Your BMI Result
15.6 kg/m² Severely Underweight

How your BMI was calculated

Formula: BMI = weight (kg) ÷ height (m)²
Your values: 45 kg ÷ (1.70 m)²
Height squared: (1.70)² = 2.8900 m²
Result: 45 ÷ 2.8900 = 15.6 kg/m²

⚖️ Ideal Weight Range

53.5 kg — 72 kg

For 1.70 m height (BMI 18.5-24.9)

🎯 Weight Goal

↑ Gain 8.5 kg

Target: 53.5 kg to reach healthy BMI

What does a BMI of 15.6 mean?

Your BMI of 15.6 kg/m² indicates you are severely underweight.

At 1.70 m (170 cm) and 45 kg, your body weight is significantly below the healthy range. A BMI below 16 may indicate malnutrition or an underlying health condition that requires medical attention.

Recommended actions:
  • Consult a healthcare provider to rule out underlying health issues
  • Work with a registered dietitian to develop a healthy weight gain plan
  • Focus on nutrient-dense foods and regular meals
  • Consider strength training to build muscle mass safely

Remember: BMI is a screening tool, not a diagnostic measure. It doesn't account for muscle mass, bone density, or where fat is distributed. Always consult healthcare professionals for personalized health advice.

How weight changes affect your BMI

See how gaining or losing a few kilograms would change your BMI category:

Weight BMI Category
41 kg -4 14.2 Severely Underweight
43 kg -2 14.9 Severely Underweight
45 kg ← you 15.6 Severely Underweight
47 kg +2 16.3 Underweight
49 kg +4 17.0 Underweight

This table shows how your BMI would change with different weights at your current height of 1.70 m.

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BMI 15.6 (Severely Underweight) — 170 cm / 45 kg
BMI 15.6 (Severely Underweight) — 170 cm / 45 kg — conversion chart

This BMI calculator is provided for informational purposes only and does not replace professional medical advice. Learn more about BMI, limitations, and health recommendations.

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