Body Shape Calculator

Background.

Dressmakers, tailors, and style guides have sorted bodies into a handful of silhouettes for a century — hourglass, pear (triangle), inverted triangle, apple (round), rectangle — because a few circumference relationships predict how garments hang better than any single size number does. This page applies one explicit version of that sorting: it compares your shoulder, bust, waist, and hip measurements against stated proportional rules and names the silhouette they satisfy, alongside your waist-to-hip ratio.

The rules are relative, which is the point. An hourglass-type classification, for instance, asks whether the upper body (the larger of shoulder and bust) and the hips are within about 5% of each other, with the waist markedly smaller — at least 20% below the hip line in the rule used here. A pear emerges when hips clearly dominate the upper body; an inverted triangle when shoulders dominate hips; a rectangle when all three zones run within a narrow band of each other. Absolute size never enters — a 90 cm-hip and a 120 cm-hip figure can share a silhouette.

What the labels are for is fit: where a garment needs room, where it needs shaping, whether off-the-rack cuts assume proportions you do not have. What they are not is anything medical or evaluative — the categories are clothing-fit heuristics with fuzzy boundaries, measured bodies frequently sit near a threshold between two labels, and no silhouette is better than another. The waist-to-hip ratio is reported as a familiar summary of the same tape measurements; population health research uses WHR under its own protocols and cutoffs, which this styling context does not reproduce.

Measure honestly — tape parallel to the floor, snug but not compressing — and treat the output as a starting vocabulary for fit decisions, as the scope note beside the result says.

What is body shape calculator?

A body-shape (silhouette) classification is a rule-based label — hourglass, pear/triangle, inverted triangle, apple/round, or rectangle — assigned from the relative proportions of shoulder or bust, waist, and hip circumferences. This page implements one explicit circumference rule set: it takes the larger of shoulder and bust as the ‘top’ measure, compares top against hips within a tolerance, and tests how much smaller the waist is than both. The waist-to-hip ratio (waist ÷ hip) is computed from the same tape readings as a compact numeric summary. All of it is descriptive tailoring vocabulary, not a health assessment.

How to use this calculator.

1. 01Measure with a soft tape over minimal clothing, parallel to the floor: shoulders at their widest point around the body, bust or chest at the fullest point, waist at the natural crease (usually the narrowest point above the navel), hips at the fullest part of the seat.
2. 02Take each measurement twice and re-measure any pair that differs — tape tension and tilt move circumferences by a centimetre or two, enough to flip a near-boundary classification.
3. 03Enter all four values in centimetres (consistency matters more than the unit — the rules are proportional).
4. 04Read the named silhouette and the waist-to-hip ratio together; if your numbers sit within a percent or two of a rule boundary, treat yourself as between categories — real bodies often are.
5. 05Use the label as fit guidance — which cuts assume your proportions — not as a target: the categories have no ranking, and none of this measures health.

The formula.

The classifier works on ratios, never absolutes. First it selects the effective upper-body girth — the larger of shoulder and bust circumference — since either can define how a garment must fit above the waist. It then applies ordered proportional tests; in the rule set used here, an hourglass-like label requires the top and hip girths to agree within 5% while the waist undercuts the hip by at least 20%. Failing that, dominance tests apply: hips exceeding the top girth beyond tolerance reads as pear-like, top exceeding hips as inverted-triangle-like, a waist not meaningfully smaller than either as rectangle- or apple-like depending on where the waist sits. The 5% and 20% thresholds are stated conventions, not natural constants — published style systems draw the lines in slightly different places, which is why the same tape measurements can earn different labels in different guides and why this page names its rule explicitly. The waist-to-hip ratio is the plain quotient of two entered values. The engine evaluates comparisons and the ratio in Decimal arithmetic, rounding the ratio once to twelve significant digits.

A worked example.

Frequently asked questions.

References& sources.

1. [1]U.S. National Institutes of Health. Health information current 2026. Evidence-based health measurement context. Retrieved 2026-08-06. independence: primary; access: open.
2. [2]U.S. National Library of Medicine. PubMed record current 2026-08-06. Indexed derivation and validation literature. Retrieved 2026-08-06. independence: secondary-check; access: open.
3. [3]World Health Organization. Patient safety resources current 2026. Clinical decision-support safety context. Retrieved 2026-08-06. independence: primary; access: open.