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Zero dependencies

Plain vanilla js

Framework Agnostic

Seamless integration with React Final Form

Seamless integration with Formik

💥 <4.5k gzipped 💥

Form schema validation library.

let's get fonky

Fonk is a pure javascript, framework agnostic, form validation library.

It allows you to:

  • Define validations that apply to your form in a declarative way.
  • Isolate your form validation business logic from the ui.
  • Unit test your form validation without having to mount the ui.
  • Create reusable validation rules that can be easily unit tested.


Live Demo (Fonk + React Final Form)

Fonk can be easily plugged into many libraries / frameworks or just be used in plain vanilla js.

Available integration examples:

Coming soon integration examples:

  • Vuejs.

How to get started

Check our Fonk Documentation site.

About Basefactor + Lemoncode

We are an innovating team of Javascript experts, passionate about turning your ideas into robust products.

Basefactor, consultancy by Lemoncode provides consultancy and coaching services.

Lemoncode provides training services.

For the LATAM/Spanish audience we are running an Online Front End Master degree, more info: