Calculate arch indices from a footprint
Mark the widest forefoot, narrowest midfoot and widest heel widths on a footprint, or enter the measurements; see the Chippaux-Smirak and Staheli indices.
Use a flat footprint image taken from directly above. The image is processed in your browser; it is never sent to a server.
Indices
Complete the three widths.
Not a diagnostic tool
A footprint is a static measurement; arch structure, flexibility and gait are assessed by clinical examination.
Who are you?
Run this measurement automatically from a scan in your clinic
In a 30-minute demo we'll show the same calculation on a 3D scan, with your own case. Your result is added to the form automatically.
Result added to the form
No calculated result yet — you can still send the form.
Frequently asked questions
What is the Chippaux-Smirak index?
It is the ratio of the narrowest midfoot width of a footprint to the widest forefoot width at the level of the metatarsal heads (× 100). The larger the value, the wider the midfoot contact area, which gives indirect information about the height of the medial arch.
What is the Staheli index?
It is the ratio of the narrowest midfoot width of a footprint to the widest heel width. It differs from the Chippaux-Smirak index by using heel width rather than forefoot width as the denominator.
Why no classification (flat / normal / high arch)?
Published thresholds for these indices vary considerably with age, sex and the population studied; there is no single threshold source. The tool therefore only calculates the ratio. Interpretation should be made by a clinician using an age-appropriate reference.
How should the footprint be taken?
Standing, with weight evenly on both feet; an ink pad print, a podoscope image or a top-down photo of a print on a flat surface can be used. Because a ratio is measured the image scale is not needed, but the photo should be flat and taken from directly above.