Ideal Weight Calculator

What this calculator estimates

Compare a legacy height-based weight estimate with the weights corresponding to adult BMI 18.5 and 24.9. The name “ideal weight” describes the formula category, not a single correct weight for every person.

Inputs and calculation method

Enter height in centimetres and select the equation option. The main result uses this tool’s height-based reference constants. The two comparison weights use height squared and the stated BMI boundaries; neither calculation uses age, body composition or current weight.

Formula and units

Convert height to inches by dividing cm by 2.54. Inches above 60 = max(0, height in inches − 60). The main reference is 48 + 2.3 × inches above 60 for the male option, or 45.5 + 2.3 × inches above 60 for the female option. BMI comparisons are 18.5 × height in metres² and 24.9 × height in metres².

How to use it

1. Enter height in cm and select the formula option.
2. Calculate and compare the main reference with the two BMI-based values.
3. Notice that this implementation does not reduce the legacy estimate below 152.4 cm.
4. Use these figures as formula references rather than instructions to reach a particular weight.

Worked example

At 165 cm with the female option, height is about 64.96 inches. The main reference is 45.5 + 2.3 × 4.96 = 56.9 kg after rounding. The BMI-based comparison weights are 50.4 kg and 67.8 kg.

How to read the result

The main value is a legacy formula result. It is not a body-composition assessment, and the BMI range does not identify an individual’s healthiest weight. Below 152.4 cm, this implementation holds the “inches above 60” term at zero.

Common mistakes

• Treating the main value as a compulsory goal.
• Expecting the formula to account for muscle, frame size or age.
• Using an adult height formula to assess a child’s growth.

Method limitations

Height-only rules cannot account for individual health, ethnicity, body composition or pregnancy. The result should not determine medication doses or clinical nutrition needs.

Sources and method references

• CDC: adult BMI calculation and screening categories

Supporting guides

• Healthy Weight Range By Height: How To Read It ProperlyA grounded guide to height-based weight ranges, BMI context, body frame, muscle mass and realistic health goals.
• Ideal Weight Calculator Guide: How To Choose A Realistic TargetUse an ideal weight calculator without chasing a random number. Learn how to turn a broad estimate into a practical first target.
• Why Ideal Weight Is A Range, Not A Single NumberThe idea of one perfect weight is flawed. This guide explains why healthy weight should be interpreted as a range.
• Ideal Weight vs BMI: Which One Should You Use?Compare ideal weight calculators and BMI so you know what each number can tell you and what each one misses.
• Healthy Weight Goals Without Crash DietingHow to set a weight goal that does not rely on extreme restriction, rebound dieting or unrealistic timelines.
• Body Frame, Muscle Mass And Ideal Weight: Why The Same Height Can Need Different TargetsWhy two people of the same height should not always aim for the same weight, especially when frame size and muscle mass differ.

Using the estimate

Read all three values as transparent formula comparisons. None establishes a personalised ideal weight.