| Formula | Ideal Weight ({{ weightUnit }}) | Copy |
|---|---|---|
| {{ r.name }} | {{ formatWeight(r.value) }} |
Ideal body weight is a height-based reference estimate rather than a single biologic truth. It is widely used as a rough planning number in settings such as clinical dosing, nutrition discussions, and personal goal-setting because height is easy to measure, but the same height can still produce different targets depending on which published equation you choose.
This calculator makes that difference visible by showing four classic formulas side by side: Devine, Hamwi, Robinson, and Miller. You select the male or female setting, enter height in centimetres or inches, and the tool returns each formula result, an average, and the overall minimum-to-maximum span in kilograms or pounds.
That comparison view is more useful than one isolated figure because the formulas are similar but not identical. At the default example of 172 cm with the male setting, the four estimates cluster between 66.7 kg and 68.8 kg, with an average of 67.6 kg. The gap is not huge, but it is large enough to matter when someone asks for a named formula instead of a generic “ideal weight” number.
A common use case is height-based planning when you need a quick reference target before moving into more nuanced assessment. The range helps you see whether the formulas agree tightly or spread farther apart, while the optional frame-size adjustment lets you test a modest shift upward or downward without changing the underlying height input.
The output should still be treated as an estimate. This package does not ask for current weight, age, body composition, pregnancy status, edema, or athletic build, and it does not try to diagnose health from the result. It also mirrors changed inputs into the page address, so avoid sharing a link that exposes personal measurements if that matters in your context.
The fastest way to use the tool is to set the male or female option, enter height, and read the summary badge first. That top summary shows the average of the four implemented formulas together with the minimum-to-maximum span, which gives you an immediate sense of where the formulas cluster before you start comparing rows one by one.
| Control | What It Changes | Why You Would Use It |
|---|---|---|
| Gender | Switches between the male and female coefficient sets used by all four formulas. | Use the setting that matches the formula convention you are trying to reproduce. |
| Height | Sets the only direct body measurement in the calculation. | Because the tool is entirely height-based, getting this value and its unit right matters more than anything else. |
| Weight unit | Changes the output display between kilograms and pounds. | Helpful when your source material, care plan, or household scale uses one unit more naturally than the other. |
| Frame size | Applies a uniform multiplier to all four formula outputs. | Useful when you want a quick sensitivity check around a medium-build baseline. |
The Formula Comparison tab is the best place to start when a protocol, article, or clinician names a specific method. You can read the exact row you need, copy a single row, copy the full comparison as CSV, download it as CSV, or export the comparison table as DOCX. If nobody requires a named formula, the average and range usually give the cleaner planning view because they show both the midpoint and the spread.
The Formula Weights chart is useful when you want to see the spread at a glance rather than read numbers line by line. The chart can be downloaded as PNG, WebP, JPEG, or CSV. The CSV export for the chart includes the four formula rows plus average, minimum, and maximum values, which is handy for a spreadsheet or note even though the plotted bars represent only the four formulas themselves.
The JSON tab is the structured record of the same state. It captures the inputs, the derived height conversion, the active frame multiplier, each named formula result, and the same comparison rows shown in the table. That makes it practical for note-taking or for confirming exactly which settings produced a saved result.
For most people, the best habit is to start with the medium frame setting, confirm the height unit, and only then test small or large frame. If a clinical protocol or a calculator elsewhere asks for Devine or Robinson specifically, use that named row. If the question is simply “what rough height-based target do these classic formulas suggest?”, use the average and range together.
The package converts the entered height to centimetres, then calculates how many inches that height exceeds 5 ft, or 152.4 cm. Extra height below that threshold is clamped at zero rather than becoming negative, so shorter values fall back to each formula's base constant. After the four kilogram estimates are computed, the tool either keeps them in kilograms or converts them to pounds using a fixed multiplier.
| Formula | Male Equation (kg) | Female Equation (kg) |
|---|---|---|
| Devine | 50 + 2.3 × h_ex |
45.5 + 2.3 × h_ex |
| Hamwi | 48 + 2.7 × h_ex |
45.5 + 2.2 × h_ex |
| Robinson | 52 + 1.9 × h_ex |
49 + 1.7 × h_ex |
| Miller | 56.2 + 1.41 × h_ex |
53.1 + 1.36 × h_ex |
The frame-size control applies a simple final multiplier to every formula: 0.9 for small, 1.0 for medium, and 1.1 for large. Because that multiplier is applied after the base formula, it shifts the entire set upward or downward by 10 percent instead of changing one formula differently from another. That makes the comparison easy to read, though it should be understood as a broad adjustment rather than a measured skeletal-frame calculation.
The summary values are derived from the same four displayed formula results. Minimum and Maximum are the outer bounds of the four outputs, while Average is the simple arithmetic mean of those same four numbers after unit conversion. The tool becomes “results ready” as soon as height is greater than zero, which is why it can update immediately without waiting for extra clinical inputs.
The current implementation has no dedicated server-side calculation step. The formula comparison, chart, and JSON payload are all generated from the same local state after the page loads. The JSON view stores the original inputs, derived values such as heightCm and heightExtraIn, the active frame multiplier, each formula result, and the summary range statistics.
One consequence of this design is that the tool is intentionally narrow. It does not estimate body fat, lean mass, BMI, or recommended calorie intake. It answers one specific question: “Given this height, this male or female setting, this frame adjustment, and these four classic formulas, what weight estimates do they produce?”
The average is not a privileged medical truth. It is simply the midpoint of the four formulas implemented here. That makes it useful as a compact planning reference, but if a medication guide, nutrition workflow, or local protocol names one formula specifically, that named row should take priority over the average.
The range tells you how much the formulas disagree for the current settings. A narrow span means the four methods are clustered tightly around the same area. A wider span means formula choice matters more. For many typical adult heights the spread is only a few kilograms, but even that difference can be meaningful in structured workflows.
The frame-size control shifts the whole set, not one row at a time. Small lowers every output by 10 percent, and large raises every output by 10 percent. Because the change is uniform, it is best read as a sensitivity check rather than as a discovery that one formula is “better” for a larger or smaller build.
Heights under 5 ft deserve special attention because the package does not subtract weight for negative extra inches. Instead, it clamps extra inches at zero, so the formulas fall back to their base constants. That is why a 150 cm male example produces 50.0 kg, 48.0 kg, 52.0 kg, and 56.2 kg rather than values lower than those baselines.
If the result looks implausible, check unit entry before interpreting the number. Switching from centimetres to inches without changing the numeric height can move the estimate dramatically, while switching output from kilograms to pounds should only change the presentation scale. The tool is best used as a height-based reference, not as a verdict on health or physique.
Default adult example. With the male setting, height 172 cm, medium frame, and kilogram output, the tool returns Devine 67.7 kg, Hamwi 68.8 kg, Robinson 66.7 kg, and Miller 67.1 kg. The average is 67.6 kg, so the practical range is a narrow 66.7 kg to 68.8 kg.
Frame-size sensitivity. With the female setting, height 165 cm, small frame, and kilogram output, the estimates fall between 50.8 kg and 53.9 kg, with an average of 51.9 kg. The same height at a larger frame setting shifts the whole set upward, which makes frame size useful for quick scenario testing when you want more than one planning band.
Below the 5 ft anchor. With the male setting at 150 cm, the tool clamps extra inches to zero. That produces the formula bases directly: Devine 50.0 kg, Hamwi 48.0 kg, Robinson 52.0 kg, and Miller 56.2 kg. If you are checking a shorter height and the numbers seem “stuck” near these baselines, that is the intended package behavior rather than a calculation error.
Because it implements four named ideal-weight formulas that use different coefficients. The average and range summarize them, but the individual rows remain visible in case you need one specific method.
No. It only changes the display unit after the kilogram result is calculated. Large differences after a unit change usually point to a height-unit mistake rather than to a real change in the estimate.
The package sets extra height above 5 ft to zero instead of going negative. That means the formulas fall back to their base constants rather than subtracting weight for shorter stature.
Use the named formula if a protocol or clinician specifies one. Use the average and range when you want a general planning reference across the four implemented methods.
No. This package is intentionally height-based. It uses the selected male or female coefficient set, height, output unit, and optional frame adjustment only.
The current implementation does not use a dedicated calculation backend, but changed inputs are mirrored into the page address. That is convenient for repeat checks, yet it is worth remembering before sharing a link that contains personal measurements.
h_ex