Fimo is a brand of polymer clay made by German company Staedtler. Fimo is sold worldwide. Its main U.S. competitor is the American brand Sculpey. The material comes in many different colors; there are many finishes to choose from, and even a softener to use with it because it can be hard to work. It is used for making many objects, including jewelry, accessories, and small ornaments. Once shaped, Fimo is baked in a standard or toaster oven for about 30 minutes at 130 °C (265 °F) to harden it. Once baked, it can be cut, drilled, painted, sanded, and sliced thinly. According to information from Staedtler, Fimo contains polyvinyl chloride (PVC), but has not contained any phthalates since 2006.

Polymer clay is a type of hardenable modeling clay based on the polymer polyvinyl chloride (PVC). It typically contains no clay minerals, but like mineral clay a liquid is added to dry particles until it achieves gel-like working properties. Similarly, the part is put into an oven to harden, hence its colloquial designation as clay. Polymer clay is generally used for making arts and craft items, and is also used in commercial applications to make decorative parts. Art made from polymer clay can now be found in major museums.