BMI Calculatorby Chaudify

How to Use the Advanced BMI & Health Analysis

This short guide explains the unit toggles, required fields, and how to read the exclusive health metrics (Cellular Age, Metabolic Health Score, Body Symmetry Index and more).

Step 1 — Choose units & enter measurements

Select Metric (kg, cm) or Imperial (lb, ft/in) from the top of the form. Enter weight and height for the chosen units. The form will show only the required fields for the unit set you choose.

Step 2 — Primary measurements to prioritize

Always provide weight and height — these are required for BMI. If entering Imperial, include both feet and inches. Use decimal values for weight when possible (e.g., 70.5 kg).

Step 3 — Add optional composition data

Add age and gender to unlock Body Fat and BMR estimates. Provide waist, hip and neck if you want the Navy body-fat calculation and improved risk context (waist-to-hip ratio).

Step 4 — Calculate and interpret results

Press Calculate to see BMI, BMI Prime, ideal weight range, body fat estimate, BMR and our exclusive metrics (Cellular Age, Metabolic Health Score, Body Symmetry Index). Each result card includes a short description to help interpretation.

Step 5 — Track changes and trends

Use the tool regularly to track trends rather than single measurements. Small fluctuations are normal; look at direction and consistency over weeks or months.

Step 6 — When to seek professional advice

These metrics are educational. If you have health concerns, unexpected changes, or need clinical accuracy (e.g., body composition for medical reasons), consult a healthcare professional for tests like DEXA or bloodwork.

Quick tips: Toggle units before typing, double-check imperial inputs (feet/inches), and prefer consistent timing/settings when tracking (same scale, same time of day).

Short glossary

  • BMI: Weight (kg) / height (m)² — screening, not diagnostic.
  • BMI Prime: BMI divided by 25 — shows relative distance from the healthy upper threshold.
  • Body Fat Estimate: Calculated from formulas; more accurate with waist/hip/neck and demographics.

Privacy note: Inputs are used for calculations and are not stored permanently by default. This tool is educational and not a substitute for medical advice.