5 Best Form Helper (Validator) Packages for Flutter in 2023

A form is a continuous process of collecting information from an individual that creates a record. In other words, it’s the set of questions you ask to get someone’s contact info or to learn about their preferences. Forms are everywhere! They’re used in places as diverse as medical offices, shopping malls, and government agencies.

Form validation helps us to ensure that the user is submitting the correct data. It can also help to prevent malicious submissions, such as spam or code injection. By validating the form data on the client-side, we can give users immediate feedback about their input. This is especially important for mobile users, who may not have the best keyboard or the easiest time submitting information.

Forms are also a key part of the web and mobile apps. When it comes to creating forms in your app, you have a few options: you can create the form’s user interface (UI) yourself, use a third-party library, or use a form builder provided by your app development platform. In this article, we’ll take a look at five of the best form helper packages for Flutter.

The Best Form Helper Packages

flutter_form_builder

This package helps remove the boilerplate needed to build a form, validate fields, react to changes, and collect final user input. Plus, it includes ready-made input fields for FormsBuilder so you can add common inputs with ease.

The currently supported fields include:

FormBuilderCheckbox – Single Checkbox field
FormBuilderCheckboxGroup – List of Checkboxes for multiple selection
FormBuilderChoiceChip – Creates a chip that acts like a radio button.
FormBuilderDateRangePicker – For selection of a range of dates
FormBuilderDateTimePicker – For Date, Time and DateTime input
FormBuilderDropdown – Used to select one value from a list as a Dropdown
FormBuilderFilterChip – Creates a chip that acts like a checkbox.
FormBuilderRadioGroup – Used to select one value from a list of Radio Widgets
FormBuilderRangeSlider – Used to select a range from a range of values
FormBuilderSegmentedControl – For selection of a value using the CupertinoSegmentedControl widget as an input
FormBuilderSlider – For selection of a numerical value on a slider
FormBuilderSwitch – On/Off switch field
FormBuilderTextField – A Material Design text field input.

formz

This powerful library makes it easy to create and validate forms in a generic way, without all the hassle. So save yourself some time – and headaches!

final validInputs = <FormzInput>[
  NameInput.dirty(value: 'may'),
  NameInput.dirty(value: 'june'),
  NameInput.dirty(value: 'december'),
];

print(Formz.validate(validInputs));

form_field_validator

It provides all the common validation options you need to ensure your data is accurate and complete. Plus, it’s easy to use and integrate into your existing code. You can add the validator property to an existing text field like this:

TextFormField(  
         validator: EmailValidator(errorText: 'enter a valid email address')  
         );

reactive_forms

If you’re looking for a model-driven approach to handling form inputs and validations, try reactive_forms! This library is heavily inspired by Angular Reactive Forms, so if you’re familiar with that library, you’ll feel right at home with reactive_forms.

final form = FormGroup({
  'name': FormControl<String>(validators: [Validators.required]),
  'email': FormControl<String>(validators: [
    Validators.required,
    Validators.email,
  ]),
});

form_validator

form_validator is a simple and reliable form validation for Flutter form widgets. It has no dependencies, supports localization, is easily extensible, and has been well tested.

TextFormField(
  validator: ValidationBuilder().email().maxLength(50).build(),
  decoration: InputDecoration(labelText: 'Email'),
),

Requirements:

Dart SDK: >=2.12.0 <3.0.0
Flutter: >= 2.8.0