“Geometric Form” (`GEOM` in CSS) is an [axis](/glossary/axis_in_variable_fonts) found in some [variable fonts](/glossary/variable_fonts) that transforms [letterforms](/glossary/letterform) from their default construction into simplified [geometric](/glossary/geometric) shapes—circles, triangles, and squares. Depending on the [typeface](/glossary/typeface), this transition can happen through a gradual reshaping of the [glyphs](/glossary/glyph), through character swaps at set points along the axis, or a combination of both.

The [Google Fonts CSS v2 API](https://developers.google.com/fonts/docs/css2) defines the axis as:

| Default: | Min: | Max: | Step: |
| --- | --- | --- | --- |
| 0 | 0 | 100 | 10 |

<figure>

![An image showing three type specimens, each with an axis slider underneath. The specimen on the left shows the default letterforms, the specimen in the middle shows that the 'a' and the 'u' have become geometric, and the specimen on the right shows that 't' is now also geometric.](images/thumbnail.svg)

<figcaption>Typeface: <a href="https://fonts.google.com/specimen/Cal+Sans">Cal Sans</a></figcaption>

</figure>

At 0, letterforms keep their regular, default construction. As the axis increases towards 100, details are progressively simplified until the [strokes](/glossary/stroke) resolve into the plain geometric shapes underlying the [typeface](/glossary/typeface)’s design. Because the axis moves in fixed increments rather than a smooth continuum, some typefaces use it to switch cleanly between a small number of named styles rather than blend infinitely between them.

This axis is best suited to [display](/glossary/display) typefaces, since strongly geometric letterforms can reduce [readability](/glossary/readability) at smaller sizes.