Ideal Weight Calculator

What's your ideal weight? Our Ideal Weight Calculator helps you find a healthy range tailored to your height, age, and gender. Whether for fitness, health checks, or weight management, this tool provides instant guidance. Simple, accurate, and free

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Ideal Weight Calculator: Guide

The modern health-conscious society depends largely on understanding your ideal body weight. Your knowledge of your ideal weight offers essential information whether you seek fitness improvement, want to manage health problems, or create a health plan for your daily life. But how do you calculate it? What formulas are most reliable? The same information demonstrates applications in real-world situations, and the steps should be followed to achieve this goal. The following article details all essential information regarding ideal weight calculation alongside practical use guidelines.

How to Calculate Ideal Weight

The weight range that doctors deem appropriate for someone falls under the category of ideal weight. Doctors consider height measurement together with gender, age, and body composition structure in their determination. Several mathematical methods were developed across the years to calculate Ideal Body Weight, although there exists no universal solution. Mathematical computations provide people with attainable weight aims and enable them to follow their health development.
Step 1: Gather Your Information
You will need several simple facts to determine your ideal weight.
Height: Measured in either inches or centimeters.
Men and women need distinct body mass calculators since their bodily makeups differ.
Certain weight calculation procedures include three categories of body frame sizes because this affects the way weight is spread throughout the body.
Step 2: Choose a Formula
Two popular methods exist to find your ideal weight among many available calculation tools, with the Peterson formula and Devine formula being the most common. Additional information about these formulas will be provided later in this article.
Step 3: Plug in the Numbers
To get an estimated ideal weight, you should enter your data into the selected formula after making your selection. The calculated results operate as guidelines because additional variables such as muscle mass and bone density shape the results.

Formulas for Finding the Ideal Weight

Many different formulas have been developed over the years to help people determine ideal weight. But all aim to provide a reliable estimate. All of these involve their own method of calculation, but each of them attempts to provide a reliable estimate. Some of the most common formulas listed below are the G. J. Hamwey formula (1964), the B. J. Devine formula (1974), the J. D. Robinson formula (1983), and the D. R. Miller formula (1983).
1. Hamwi Formula of G. J. (1964)
One of the earliest and most popular formulae for determining ideal weight is the Hamwi Formula. It is easy and takes only gender and height. That is how it works:
Male: 106 pounds at 5 feet height. Add 6 pounds to every additional inch.
Women: To begin with, use 100 pounds at the initial 5 feet of height. To every added inch, add 5 pounds.
As an example, an average woman who is 5 feet 6 inches tall and her ideal weight would be: 100 pounds (being 5 feet) + (5 pounds per inch x 6 inches) = 130 pounds.
It is a simple formula that fails to consider age or body composition (such as muscle mass); thus, it is an estimation rather than a final answer.

2. B. J. Devine Formula (1974)
The Devine Formula was originally developed for medical purposes, like calculating drug dosages, but it's now used for ideal weight estimation. It's similar to the Hamwi Formula but slightly different:
For Men: 50 kg (110 pounds) + 2.3 kg (5.1 pounds) for each inch over 5 feet.
For Women: 45.5 kg (100 pounds) + 2.3 kg (5.1 pounds) for each inch over 5 feet.
For a 5'6” inches tall woman: 45.5 kg + (2.3 kg × 6 inches) = 45.5 kg + 13.8 kg = 59.3 kg (about 130.7 pounds).
This formula is popular in medical settings because it's simple and provides consistent results.

3. J. D. Robinson Formula (1983)
The Robinson Formula tweaks the Devine Formula to account for slight differences in body structure:
For Men: 52 kg (114.6 pounds) + 1.9 kg (4.2 pounds) for each inch over 5 feet.
For Women: 49 kg (108 pounds) + 1.7 kg (3.7 pounds) for each inch over 5 feet.
For a 5'6" inches tall woman: 49 kg + (1.7 kg × 6 inches) = 49 kg + 10.2 kg = 59.2 kg (about 130.5 pounds).
This formula is considered a bit more modern and refined than the Devine Formula.

4. D. R. Miller Formula (1983)
The Miller Formula is another variation that adjusts the numbers slightly:
For Men: 56.2 kg (123.9 pounds) + 1.41 kg (3.1 pounds) for each inch over 5 feet.
For Women: 53.1 kg (117 pounds) + 1.36 kg (3 pounds) for each inch over 5 feet.
For a 5'6" inches tall woman: 53.1 kg + (1.36 kg × 6 inches) = 53.1 kg + 8.16 kg = 61.26 kg (about 135 pounds).
Each formula gives slightly different results, so it's helpful to use them as a range rather than a single number. Factors like muscle mass, bone density, and lifestyle can influence what's “ideal” for you.

Ideal Weight Calculation Example

Let's go through an example, and this will be clearer. Suppose we will calculate the ideal weight for a 5'8" inches tall male with all four formulas,

Hamwi Formula:
106 pounds + (6 pounds × 8 inches) = 106 + 48 = 154 pounds.

Devine Formula:
50 kg + (2.3 kg × 8 inches) = 50 kg + 18.4 kg = 68.4 kg (about 150.8 pounds).

Robinson Formula:
52 kg + (1.9 kg × 8 inches) = 52 kg + 15.2 kg = 67.2 kg (about 148.2 pounds).

Miller Formula:
56.2 kg + (1.41 kg × 8 inches) = 56.2 kg + 11.28 kg = 67.48 kg (about 148.7 pounds).
For a 5'8" inches tall man, this “ideal” weight range of roughly 148-154 pounds, depending on the formula. This range is a good starting point, but talking to a doctor or a nutritionist is even more helpful to find a personalized rather than a one-size-fits-all approach.

BMI for Children & Teens

In children and adolescents (between 2 and 19 years), BMI is explained differently, given that the body is not fully developed yet. The comparison of a child's BMI with that of other children of the same age and gender is done using percentiles instead of fixed ranges. These categories are given by the CDC:

As an example, a 15-year-old boy who is 5'6" inches and weighs 130 pounds could be at the 50th percentile, which means his BMI is average as compared to other boys of his age. Growth charts are of use to the pediatricians to track this over time.

Healthy BMI Range for Adults (WHO Standards)

For adults (age 20 and older), the healthy BMI range is 18.5-24.9, according to the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC). Here's what the categories mean:

For example, a 5'6" inches tall person weighing 130 pounds has a BMI of: (130 × 703) ÷ (66 inches)² = 91,390 ÷ 4,356 = 21.0 (normal weight).
BMI isn't perfect—it doesn't account for muscle mass or body composition—but it's a useful guideline.