Reference · eight ratios Body proportion chart
Formulas, reference ranges and the difference between a measured average and an artistic
canon. Use the calculator for your own numbers; use this page to see what each number means.
A proportion chart is only useful if it says which reference it is using. This one separates
three kinds of number: a measured population average, a clinical reference point (waist
ratios only), and an artistic canon. The label matters more than the decimal.
| Ratio | Formula | Reference | Primary use |
|---|
| Heads tall | height ÷ head height | Adults usually fall around 7–7.5; the classical canon uses 8. | Drawing |
| Leg-to-height | inseam ÷ height | Commonly around 45%; roughly 43–48% in many adult samples. | Fit |
| Sitting height ratio | sitting height ÷ height | About 0.52 in European samples, 0.51 in African samples, 0.53–0.54 in Asian samples; 0.48–0.55 is a broad range. | Fit |
| Shoulder-to-hip | shoulder circumference ÷ hip circumference | Descriptive: near 1.00 means the two circumferences are similar. There is no universal target. | Fit |
| Shoulder-to-waist | shoulder circumference ÷ waist circumference | A popular physique benchmark is 1.618; it is a training convention, not a clinical standard. | Fit |
| Arm span-to-height | arm span ÷ height | Close to 1.00. Measured means were 0.96 for men and 0.92 for women in a 2020 US Air Force sample. | Fit + drawing |
| Waist-to-hip | waist circumference ÷ hip circumference | WHO reference points: 0.85 for women and 0.90 for men, above which abdominal obesity is considered present. | Health |
| Waist-to-height | waist circumference ÷ height | Common guidance: keep it under 0.50; 0.50–0.59 is above; 0.60 or more is the top of the range. | Health |
height ÷ head height
- Reference
- Adults usually fall around 7–7.5; the classical canon uses 8.
- For fit
- A quick check of overall frame proportion. It is not a garment-fit measurement on its own.
- For drawing
- The basic unit of figure drawing: about 7.5 heads for a naturalistic adult, 8 for an idealised classical figure.
- Caution
- Head height is crown to chin. A different head-height definition changes the number.
inseam ÷ height
- Reference
- Commonly around 45%; roughly 43–48% in many adult samples.
- For fit
- How much of your height sits below the crotch. Useful when comparing rise, inseam and high-rise versus long-leg silhouettes.
- For drawing
- Legs are usually 3.5–4 heads long in the classical canon; a longer leg line reads as fashion illustration.
- Caution
- There is no single definition of leg length. This calculator uses the inseam (floor to crotch).
sitting height ÷ height
- Reference
- About 0.52 in European samples, 0.51 in African samples, 0.53–0.54 in Asian samples; 0.48–0.55 is a broad range.
- For fit
- The torso-versus-leg share of your height. A higher ratio means a longer torso relative to the legs.
- For drawing
- A low ratio gives a longer leg line; a high ratio gives a longer torso. Neither is “better”.
- Caution
- Measure sitting height from the seat to the top of the head, not from the floor.
shoulder circumference ÷ hip circumference
- Reference
- Descriptive: near 1.00 means the two circumferences are similar. There is no universal target.
- For fit
- The balance of upper and lower width. Useful when choosing where to add volume in a jacket, shirt, skirt or trouser.
- For drawing
- Shoulder width is usually about two heads in the classical canon. This card uses circumferences, so it is not the same as a straight-line width drawing.
- Caution
- This is a circumference ratio, not a shoulder-width ÷ hip-width ratio. The two are not interchangeable.
shoulder circumference ÷ waist circumference
- Reference
- A popular physique benchmark is 1.618; it is a training convention, not a clinical standard.
- For fit
- How much taper the torso has. A higher number means a larger difference between shoulder and waist circumference.
- For drawing
- A higher ratio reads as a V-taper; the classical male canon uses broad shoulders and a narrower waist.
- Caution
- A fitness benchmark, not a health measure or a target everyone should chase.
arm span ÷ height
- Reference
- Close to 1.00. Measured means were 0.96 for men and 0.92 for women in a 2020 US Air Force sample.
- For fit
- Sleeve length and jacket reach. Arm span is not the same as shoulder width.
- For drawing
- The Vitruvian ideal is a 1:1 square; real bodies usually sit a little under that.
- Caution
- The measured means come from a specific US military sample, not a global average.
waist circumference ÷ hip circumference
- Reference
- WHO reference points: 0.85 for women and 0.90 for men, above which abdominal obesity is considered present.
- For fit
- Where the waist sits relative to the hip. It affects waistband, belt and high-rise versus low-rise fit.
- For drawing
- Artists have used waist-to-hip ratios as a stylistic signal for centuries; it is not a drawing rule.
- Caution
- A health reference point, not a diagnosis. Athletes, older adults and different populations can sit on either side without the same meaning.
waist circumference ÷ height
- Reference
- Common guidance: keep it under 0.50; 0.50–0.59 is above; 0.60 or more is the top of the range.
- For fit
- Waist relative to overall height. Useful for comparing high-waist and low-waist proportions without relying on absolute size.
- For drawing
- A quick check of torso-to-height balance, not an artistic canon.
- Caution
- Guidelines differ slightly in where the bands start and stop. It is not a diagnosis.
How to use the chart without over-reading it
- Pick the ratio that matches your question. For a pattern or a garment, start with waist-to-hip and shoulder-to-waist. For a drawing, start with heads tall.
- Check the definition. Inseam, sitting height and shoulder circumference are not interchangeable with other “leg length” or “shoulder width” measures.
- Read the reference as context. A value outside the band is a data point, not a verdict.
The method page lists the formulas and sources in one place. The
drawing guide covers the head-unit method in more depth.
Chart questions
Which ratio should I start with?
Height plus head height gives heads tall, the fastest overall proportion check. Height plus inseam gives leg-to-height. If you are choosing clothes, waist-to-hip and shoulder-to-waist are more directly useful than heads tall.
Why do the reference bands overlap so much?
Because the bands describe where most people sit, not a narrow target. A value just outside a band is usually a normal variation, not a problem. The bands are there to give the number context.
Why are there no “good” and “bad” labels?
A proportion is a description. The only ratios with health reference points here are waist-to-hip and waist-to-height, and those are framed as reference points, not diagnoses. Everything else is for fit or drawing.
Sources
- Revisiting Vitruvian Man (2020). Revisiting Leonardo da Vinci’s Vitruvian Man Using Contemporary Measurements. PMC7284298 (2020). https://pmc.ncbi.nlm.nih.gov/articles/PMC7284298/
63,623 men and 1,385 women from US Air Force body-scan data. Head height 0.14/0.15 of stature; arm span 0.96/0.92; shoulder width 0.24/0.25.
- Bogin & Varela-Silva (2010). Bogin, B., & Varela-Silva, M. I. (2010). Leg length, body proportion, and health: a review with a note on beauty. International Journal of Environmental Research and Public Health, 7(3), 1047–1075. https://pmc.ncbi.nlm.nih.gov/articles/PMC2872302/
Explains why leg length has no single definition: inseam, iliac height and subischial leg length give different ratios.
- Pheasant (1986) / UNU. Pheasant, S. (1986). Bodyspace: Anthropometry, Ergonomics and the Design of Work. Cited in the UNU open chapter “The effect of shape”. https://archive.unu.edu/unupress/food2/UID10E/UID10E06.HTM
Sitting-height-to-stature ratios: about 0.52 European, 0.51 African, 0.53–0.54 Asian; 0.48–0.55 across populations.
- WHO waist circumference and waist–hip ratio. World Health Organization. Waist circumference and waist–hip ratio: report of a WHO expert consultation (2008). https://www.who.int/publications/i/item/9789241501491
Waist–hip ratio reference points of 0.85 for women and 0.90 for men.
- NICE (2022) waist-to-height guidance. National Institute for Health and Care Excellence (2022). Keep your waist to less than half your height. https://www.nice.org.uk/guidance/cg189/resources
The “less than half your height” public guidance; bands differ slightly between guidelines.
- Artists Network: 7.5-head figure. Artists Network. Drawing the Proportions of the Human Body. Ameral, 2010. https://www.artistsnetwork.com/art-techniques/drawing-proportions-human-body-ameral/
A 7.5-head figure is the standard used in many realist schools; most adults are about 7–7.5 heads.
- Practical Drawing: the eight-head canon. Practical Drawing, Chapter 2 (Wikisource). The classical canon of eight heads and its use in idealised figures. https://en.wikisource.org/wiki/Practical_Drawing/Chapter_2
The eight-head canon is an artistic convention for dignity and grandeur, not a population average.