Sandy McFadden

This is a very simple plugin which requires almost no configuration.
All you need to do is go to the Appearence then Widgets area in the Admin Dashboard. 
Once you are there drag the BMI Calculator widget onto the widget area you would like it added to.
The only two settings are the title and the color. The color is the hex color you would like the results background to be.
A lot of the code was adapted from 
<a href="http://codereview.stackexchange.com/questions/21581/calculating-body-mass-index-bmi" title="Inspiration Code" rel="nofollow ugc">Stack Exchange Thread</a>

Healthy BMI Calculator

Adds a shortcode and widget that will display a simple BMI Calculator on your site. Works with both metric and US style measurements.

codepeople

The plugin implements the “Fitness and Health” operations module to be used from the equations of the <a href="https://wordpress.org/plugins/calculated-fields-form/" rel="ugc">“Calculated Fields Form”</a> plugin. The “Calculated Fields Form” plugin is a form builder with a lot of potential, and its “Calculated” control is one of its great strengths. It allows you to enter mathematical formulas, determine the distance between addresses, plot graphs, process dates, manage files, and many other operations.
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The “CFF Fitness and Health Operations” plugin enhances, even more, the possibilities of the <a href="https://wordpress.org/plugins/calculated-fields-form/" rel="ugc">“Calculated Fields Form”</a> plugin, including essential operations in fitness or health-related projects as listed below:
BMI: Calculates the Body Mass Index based on the user’s height and weight. It accepts three parameters: weight (in Kg), height (in meters), and textual output (true or false) (optional, default false). When the textual output is true, the operation result would be any of the following texts: Severe Thinness, Moderate Thinness, Mild Thinness, Normal, Overweight, Obese Class I, Obese Class II, Obese Class III.
Ex: BMI(85, 1.65) Result: 31.2 
Ex: BMI(85, 1.65, true) Result: Obese Class I 
For weight in pounds, divide its value by 2.2. Ex: BMI(187/2.2, 1.65) Result: 31.2 
For heights in feet and inches, 1 foot = 0.3048 m and 1 in = 0.0254 m. Ex: If the user’s height is 5 ft and 4.96 in BMI(85, 50.3048+4.960.0254) Result: 31.2
BFP: The Body Fat Percentage calculator estimates the total body fat percentage. It accepts five parameters: weight (in Kg), height (in meters), gender (male or 0, female or 1), age (in years), and textual output (true or false) (optional, default false). When the textual output is true, the operation result would be any of the following texts: Underfat, Healthy, Overweight, Obese.
Ex: BFP(85, 1.65, "male", 44) Result: 31.39 
Ex: BFP(85, 1.65, "male", 44, true) Result: Obese 
For weight in pounds, divide its value by 2.2. Ex: BFP(187/2.2, 1.65, "male", 44) Result: 31.39 
For heights in feet and inches, 1 foot = 0.3048 m and 1 in = 0.0254 m. Ex: If the user’s height is 5 ft and 4.96 in BFP(85, 50.3048+4.960.0254, "male", 44) Result: 31.39
BMR: The Basal Metabolic Rate calculator estimate the number of calories a person needs to consume each day. It accepts five parameters: weight (in Kg), height (in meters), gender (male or 0, female or 1), age (in years), and activity level (bmr, sedentary, light, moderate, active, very, extra)
bmr: amount of energy expended per day at rest. 
sedentary: little or no exercise. 
light: exercise 1-3 times/week. 
moderate: exercise 4-5 times/week. 
active: daily exercise or intense exercise 3-4 times/week. 
very: intense exercise 6-7 times/week. 
extra: very intense exercise daily, or physical job.
Ex: BMR(85, 1.65, "male", 44, "sedentary") Result: 2000 
For weight in pounds, divide its value by 2.2. Ex: BMR(187/2.2, 1.65, "male", 44, "sedentary") Result: 2000 
For heights in feet and inches, 1 foot = 0.3048 m and 1 in = 0.0254 m. Ex: If the user’s height is 5 ft and 4.96 in BMR(85, 50.3048+4.960.0254, "male", 44, "sedentary") Result: 2000
WEIGHTGOAL: The Goal Weight Calculator estimates the number of calories a person needs to consume each day to reach his/her goal weight. It accepts six parameters: weight (in Kg), height (in meters), gender (male or 0, female or 1), age (in years), and activity level (bmr, sedentary, light, moderate, active, very, extra), goal (maintain, mild loss, loss, extreme loss, mild gain, gain, fast gain)
Ex: WEIGHTGOAL(85, 1.65, "male", 44, "sedentary", "mild loss") Result: 1725 
For weight in pounds, divide its value by 2.2. Ex: WEIGHTGOAL(187/2.2, 1.65, "male", 44, "sedentary", "mild loss") Result: 1725 
For heights in feet and inches, 1 foot = 0.3048 m and 1 in = 0.0254 m. Ex: If the user’s height is 5 ft and 4.96 in WEIGHTGOAL(85, 50.3048+4.960.0254, "male", 44, "sedentary", "mild loss") Result: 1725
IBW: The Ideal Body Weight Calculator estimates ideal weight (in Kg) based on the person height, and gender. It accepts two parameters: height (in meters), and gender (male or 0, female or 1)
Ex: IBW(1.65, "male") Result: 61.41 
For heights in feet and inches, 1 foot = 0.3048 m and 1 in = 0.0254 m. Ex: If the user’s height is 5 ft and 4.96 in IBW(50.3048+4.960.0254, "male") Result: 61.41
PREGNANCY: Determines the conception or due dates based on the first day of last menstrual period. It accepts three parameters: date, date format (Ex. dd/mm/yyyy), and output (due or 0, conception or 1)
Ex: PREGNANCY("05/14/2022", "mm/dd/yyyy", "due") Result: 02/18/2023 
Ex: PREGNANCY("05/14/2022", "mm/dd/yyyy", "conception") Result: 05/28/2022
<h3>Use</h3>
The “CFF Fitness and Health Operations” plugin includes the new “Fitness and Health” entry (see screenshots) in the operations list of the calculated fields (Insert a calculated field in the form and scroll down the operations list in your configuration). Once the “Fitness and Health” option is selected, the plugin enables the operations set and documentation. By clicking on the operation buttons, they are added to the equation’s editor.

CFF Fitness and Health Operations


The CFF is a versatile plugin with countless possibilities, and the Fitness and Health operations plugin increases its potential even more.


Extending CFF

Implements fitness and health operations module to use with the Calculated Fields Forms equations.

Healthy BMI Calculator vs CFF Fitness and Health Operations