deform is a Python HTML form generation library. It runs under Python 2.x, 3.x and PyPy.

Deform is a Python form library for generating HTML forms on the server side. Date and time picking widgets, rich text editors, forms with dynamically added and removed items and a few other complex use cases are supported out of the box.

Deform integrates with the Pyramid web framework and several other web frameworks. Deform comes with Chameleon templates and Bootstrap 3 styling. Under the hood, Colander schemas are used for serialization and validation. The Peppercorn library maps HTTP form submissions to nested structure.

Although Deform uses Chameleon templates internally, you can embed rendered Deform forms into any template language.

Demonstration Site

Visit to view an application which demonstrates most of Deform's features. The source code for this application is also available in the deformdemo package on GitHub.


The design of deform is heavily influenced by the formish form generation library. Some might even say it's a shameless rip-off; this would not be completely inaccurate. It differs from formish mostly in ways that make the implementation (arguably) simpler and smaller.

Without these people, this software would not exist:

Index and Glossary