Newforms takes care of a number of common form-related tasks. Using it, you can:

  • Display a form with automatically generated form widgets.
  • Automatically keep a JavaScript object in sync with current user input.
  • Check user input against a set of validation rules.
  • Update form display with validation errors.
  • Convert valid user input to the relevant JavaScript data types.


The core concepts newforms deals with are:


Widgets create ReactElement objects for form inputs.

For example, a Select widget knows which <option> values and labels it should generate and how to generate a <select> with the <option> corresponding to given user input data marked as selected.


A Field holds metadata about displaying a form input and validating a piece of user input. Its metadata is the source for:

  • Configuring a suitable Widget to generate a form input, with a label and help text.
  • Validating user input and providing an appropriate error message when it’s invalid.
  • Converting valid user input to an appropriate JavaScript data type.

For example, an IntegerField makes sure that its user input data is a valid integer, is valid according to any additional rules defined – such as minValue – and converts valid user input to a JavaScript Number. By default, it configures a NumberInput widget to display an <input type="number"> for input.


Forms group related Fields together, using them to validate user input and providing helpers for displaying them as HTML.

Forms drive the validation process, holding raw user input data, validation error messages and “cleaned” data which has been validated and type-converted.

Form objects

Form constructors are created by extending forms.Form and declaratively specifying field names and metadata:

var ContactForm = forms.Form.extend({
  subject: forms.CharField({maxLength: 100}),
  message: forms.CharField(),
  sender: forms.EmailField(),
  ccMyself: forms.BooleanField({required: false})

A form is composed of Field objects. In this case, our form has four fields: subject, message, sender and ccMyself. CharField, EmailField and BooleanField are just three of the available field types – a full list can be found in Form fields.

  • A form with no user input data will render as empty or will contain any default values it was configured with.
  • Once a form has user input data, it can validate it. If a form is rendered with invalid input data, it can include error messages telling the user what to correct.

Processing input data with a Form

When a form is given valid input data, the successfully validated form data will be in the form.cleanedData object. This data will have been converted into JavaScript types for you, where necessary.

In the above example, ccMyself will be a boolean value. Likewise, fields such as IntegerField and DateField convert values to a JavaScript Number and Date, respectively.

Displaying a Form

Newforms provides a React component which implements default rendering of Form objects.

This only provides rendering of the form’s own fields; it’s up to you to provide the surrounding <form> element, submit buttons etc:

render: function() {
  return <form action="/contact" method="POST" onSubmit={this.onSubmit}>
    <forms.RenderForm form={ContactForm}/>
      <input type="submit" value="Submit"/>{' '}
      <input type="button" value="Cancel" onClick={this.onCancel}/>

RenderForm will output each form field and accompanying label wrapped in a <div>. Here’s the output for our example component:

<form action="/contact" method="POST">
    <div><label for="id_subject">Subject:</label> <input maxlength="100" type="text" name="subject" id="id_subject"></div>
    <div><label for="id_message">Message:</label> <input type="text" name="message" id="id_message"></div>
    <div><label for="id_sender">Sender:</label> <input type="email" name="sender" id="id_sender"></div>
    <div><label for="id_ccMyself">Cc myself:</label> <input type="checkbox" name="ccMyself" id="id_ccMyself"></div>
  <div><input type="submit" value="Submit"> <input type="button" value="Cancel"></div>

Note that each form field has an id attribute set to id_<field-name>, which is referenced by the accompanying label tag. You can customise the way in which labels and ids are generated.

You can customise the output of RenderForm by passing certain props or a child React component. See the documentation for custom rendering for more info.

You can also completely customise form display using rendering helpers for each field.


Newforms was developed to be independent of the DOM, so it can be used on the server as well as the browser. This allows you to use it when pre-rendering initial HTML on the server, to be rehydrated and reused by React on the client side.

User inputs generated by newforms have unique name attributes and its handling of input data is compatible with POST data which would be submitted for the user inputs it generates, so you can also use it to validate regular form submissions on the server and redisplay with errors, should you need to.

This makes newforms suitable for creating apps which use good old HTTP round tripping, or for JavaScript apps which need to be capable of falling back to being usable as regular forms ‘n links webapps in any device.

For an example of using newforms this way, check out the Isomorphic Lab demo and its source on GitHub.