# Introduction

> This document is the Markdown version of [formisch.dev/react/guides/introduction/](https://formisch.dev/react/guides/introduction/). For the complete documentation index, see [llms.txt](https://formisch.dev/llms.txt).

Formisch is a schema-based, headless form library for React. It manages form state and validation. It is type-safe, fast by default and its bundle size is small due to its modular design. Try it out in our [playground](/playground/login/)!

## Highlights

- Small bundle size starting at 2.5 kB
- Schema-based validation with Valibot
- Type safety with autocompletion in editor
- Open source and fully tested with 100% coverage
- It's fast – re-renders only if necessary
- Minimal, readable and well thought out API
- Supports all native HTML form fields

## Example

Every form starts with the [`useForm`](/react/api/useForm.md) hook. It initializes your form's store based on the provided Valibot schema and infers its types. Next, wrap your form in the [`<Form />`](/react/api/Form.md) component. It's a thin layer around the native `<form />` element that handles form validation and submission. Then, you can access the state of a field with the [`useField`](/react/api/useField.md) hook or the [`<Field />`](/react/api/Field.md) component to connect your inputs.

```tsx
import { Field, Form, useForm } from '@formisch/react';
import * as v from 'valibot';

const LoginSchema = v.object({
  email: v.pipe(v.string(), v.email()),
  password: v.pipe(v.string(), v.minLength(8)),
});

export default function LoginPage() {
  const loginForm = useForm({
    schema: LoginSchema,
  });

  return (
    <Form of={loginForm} onSubmit={(output, event) => console.log(output)}>
      <Field of={loginForm} path={['email']}>
        {(field) => (
          <div>
            <input {...field.props} value={field.input} type="email" />
            {field.errors && <div>{field.errors[0]}</div>}
          </div>
        )}
      </Field>
      <Field of={loginForm} path={['password']}>
        {(field) => (
          <div>
            <input {...field.props} value={field.input} type="password" />
            {field.errors && <div>{field.errors[0]}</div>}
          </div>
        )}
      </Field>
      <button type="submit">Login</button>
    </Form>
  );
}
```

In addition, Formisch offers several functions (we call them "methods") that can be used to read and manipulate the form state. These include [`focus`](/methods/api/focus.md), [`getDeepErrorEntries`](/methods/api/getDeepErrorEntries.md), [`getDeepErrors`](/methods/api/getDeepErrors.md), [`getDirtyInput`](/methods/api/getDirtyInput.md), [`getDirtyPaths`](/methods/api/getDirtyPaths.md), [`getErrors`](/methods/api/getErrors.md), [`getInput`](/methods/api/getInput.md), [`handleSubmit`](/methods/api/handleSubmit.md), [`insert`](/methods/api/insert.md), [`isDirty`](/methods/api/isDirty.md), [`isEdited`](/methods/api/isEdited.md), [`isTouched`](/methods/api/isTouched.md), [`isValid`](/methods/api/isValid.md), [`move`](/methods/api/move.md), [`pickDirty`](/methods/api/pickDirty.md), [`remove`](/methods/api/remove.md), [`replace`](/methods/api/replace.md), [`reset`](/methods/api/reset.md), [`setErrors`](/methods/api/setErrors.md), [`setInput`](/methods/api/setInput.md), [`submit`](/methods/api/submit.md), [`swap`](/methods/api/swap.md) and [`validate`](/methods/api/validate.md). These methods allow you to control the form programmatically.

## Comparison

What makes Formisch unique is its framework-agnostic core, which is fully native to the framework you are using. It works by inserting framework-specific reactivity blocks when the core package is built, giving you native performance for any UI update. A modular methods API keeps bundles starting at just ~2.5 kB by only including the methods you import, and end-to-end type safety covers deeply nested paths and field arrays with TypeScript inference that stays fast even as forms grow.

For a side-by-side look at how Formisch compares to React Hook Form and TanStack Form, see the [comparison guide](/react/guides/comparison.md).

## Vision

My vision for Formisch is to create a framework-agnostic platform similar to [Vite](https://vite.dev/), but for forms — a shared core that lets the same mental model and codebase work natively across every modern UI framework.

## Feedback

Find a bug or have an idea how to improve the library? Please fill out an [issue](https://github.com/open-circle/formisch/issues/new). Together we can make forms even better!

## License

This project is available free of charge and licensed under the [MIT license](https://github.com/open-circle/formisch/blob/main/LICENSE.md).