C Program To Calculate BMI and BMI Category

The Body Mass Index (BMI) is defined as ratio of the weight of a person(in kilograms) to the square of the height(in meters). Write a C program that receives weight and height, calculates the BMI, and reports the BMI category as per the following table:

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Formula To Calculate Body Mass Index (BMI)

bmi = weight / (height x height);

Logic To Calculate BMI and BMI Category

We ask the user to enter weight in kelogram(kg) and height in meters(m). Then using above formula we calculate BMI(Body Mass Index). Next, by referring to the chart below we display the BMI category.

For BMI Category Ideal:
bmi >= 18.6 && bmi <= 24.9

Expected Output for the Input

User Input:
Enter height in meter
1.4
Enter weight in kg
60

Output:
Your Body Mass Index(BMI) is 30.612246
Your BMI category is: Obese

Video Tutorial: C Program To Calculate BMI and BMI Category

Source Code: C Program To Calculate BMI and BMI Category

#include < stdio.h >
int main()
{
    float height, weight, bmi;

    printf("Enter height in meter\n");
    scanf("%f", &height);

    printf("Enter weight in kg\n");
    scanf("%f", &weight);

    bmi = weight / (height * height);

    printf("Your Body Mass Index(BMI) is %f\n", bmi);

    if(bmi < 15)
    {
        printf("Your BMI category is: Starvation\n");
    }
    else if(bmi >= 15.1 && bmi <= 17.5)
    {
        printf("Your BMI category is: Anorexic\n");
    }
    else if(bmi >= 17.6 && bmi <= 18.5)
    {
        printf("Your BMI category is: Underweight\n");
    }
    else if(bmi >= 18.6 && bmi <= 24.9)
    {
        printf("Your BMI category is: Ideal\n");
    }
    else if(bmi >= 25 && bmi <= 25.9)
    {
        printf("Your BMI category is: Overweight\n");
    }
    else if(bmi >= 30 && bmi <= 30.9)
    {
        printf("Your BMI category is: Obese\n");
    }
    else if(bmi >= 40)
    {
        printf("Your BMI category is: Morbidly Obese\n");
    }
    else
    {
        printf("Wrong entry\n");
    }

    return 0;
}

Output 1:
Enter height in meter
0.8
Enter weight in kg
80
Your Body Mass Index(BMI) is 125.000000
Your BMI category is: Morbidly Obese

Output 2:
Enter height in meter
1.4
Enter weight in kg
50
Your Body Mass Index(BMI) is 25.510204
Your BMI category is: Overweight

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