TanStack Form

This guide explores how to build forms using TanStack Form. You'll learn to create forms with the `` component, implement schema validation with Zod, handle errors, and ensure accessibility.

Demo

We'll start by building the following form. It has a simple text input and a textarea. On submit, we'll validate the form data and display any errors.

}> Note: For the purpose of this demo, we have intentionally disabled browser validation to show how schema validation and form errors work in TanStack Form. It is recommended to add basic browser validation in your production code.

Component preview · Base UI
form-tanstack-demo

Approach

This form leverages TanStack Form for powerful, headless form handling. We'll build our form using the `` component, which gives you complete flexibility over the markup and styling.

• Uses TanStack Form's useForm hook for form state management.
• form.Field component with render prop pattern for controlled inputs.
• `` components for building accessible forms.
• Client-side validation using Zod.
• Real-time validation feedback.

Anatomy

Here's a basic example of a form using TanStack Form with the `` component.

<form
  onSubmit={(e) => {
    e.preventDefault()
    form.handleSubmit()
  }}
>
  <FieldGroup>
    <form.Field
      name="title"
      children={(field) => {
        const isInvalid =
          field.state.meta.isTouched && !field.state.meta.isValid
        return (
          <Field data-invalid={isInvalid}>
            <FieldLabel htmlFor={field.name}>Bug Title</FieldLabel>
            <Input
              id={field.name}
              name={field.name}
              value={field.state.value}
              onBlur={field.handleBlur}
              onChange={(e) => field.handleChange(e.target.value)}
              aria-invalid={isInvalid}
              placeholder="Login button not working on mobile"
              autoComplete="off"
            />
            <FieldDescription>
              Provide a concise title for your bug report.
            </FieldDescription>
            {isInvalid && <FieldError errors={field.state.meta.errors} />}
          </Field>
        )
      }}
    />
  </FieldGroup>
  <Button type="submit">Submit</Button>
</form>

Form

Create a schema

We'll start by defining the shape of our form using a Zod schema.

}> Note: This example uses zod v3 for schema validation. TanStack Form integrates seamlessly with Zod and other Standard Schema validation libraries through its validators API.

import * as z from "zod"

const formSchema = z.object({
  title: z
    .string()
    .min(5, "Bug title must be at least 5 characters.")
    .max(32, "Bug title must be at most 32 characters."),
  description: z
    .string()
    .min(20, "Description must be at least 20 characters.")
    .max(100, "Description must be at most 100 characters."),
})

Set up the form

Use the useForm hook from TanStack Form to create your form instance with Zod validation.

import { useForm } from "@tanstack/react-form"
import { toast } from "sonner"
import * as z from "zod"

const formSchema = z.object({
  // ...
})

export function BugReportForm() {
  const form = useForm({
    defaultValues: {
      title: "",
      description: "",
    },
    validators: {
      onSubmit: formSchema,
    },
    onSubmit: async ({ value }) => {
      toast.success("Form submitted successfully")
    },
  })

  return (
    <form
      onSubmit={(e) => {
        e.preventDefault()
        form.handleSubmit()
      }}
    >
      {/* ... */}
    </form>
  )
}

We are using onSubmit to validate the form data here. TanStack Form supports other validation modes, which you can read about in the documentation.

Build the form

We can now build the form using the form.Field component from TanStack Form and the `` component.

View complete source: form.tsx

Done

That's it. You now have a fully accessible form with client-side validation.

When you submit the form, the onSubmit function will be called with the validated form data. If the form data is invalid, TanStack Form will display the errors next to each field.

Validation

Client-side Validation

TanStack Form validates your form data using the Zod schema. Validation happens in real-time as the user types.

import { useForm } from "@tanstack/react-form"

const formSchema = z.object({
  // ...
})

export function BugReportForm() {
  const form = useForm({
    defaultValues: {
      title: "",
      description: "",
    },
    validators: {
      onSubmit: formSchema,
    },
    onSubmit: async ({ value }) => {
      console.log(value)
    },
  })

  return <form onSubmit={/* ... */}>{/* ... */}</form>
}

Validation Modes

TanStack Form supports different validation strategies through the validators option:

Mode	Description
"onChange"	Validation triggers on every change.
"onBlur"	Validation triggers on blur.
"onSubmit"	Validation triggers on submit.

const form = useForm({
  defaultValues: {
    title: "",
    description: "",
  },
  validators: {
    onSubmit: formSchema,
    onChange: formSchema,
    onBlur: formSchema,
  },
})

Displaying Errors

Display errors next to the field using ``. For styling and accessibility:

• Add the data-invalid prop to the `` component.
• Add the aria-invalid prop to the form control such as , , ``, etc.

<form.Field
  name="email"
  children={(field) => {
    const isInvalid = field.state.meta.isTouched && !field.state.meta.isValid

    return (
      <Field data-invalid={isInvalid}>
        <FieldLabel htmlFor={field.name}>Email</FieldLabel>
        <Input
          id={field.name}
          name={field.name}
          value={field.state.value}
          onBlur={field.handleBlur}
          onChange={(e) => field.handleChange(e.target.value)}
          type="email"
          aria-invalid={isInvalid}
        />
        {isInvalid && <FieldError errors={field.state.meta.errors} />}
      </Field>
    )
  }}
/>

Working with Different Field Types

Input

• For input fields, use field.state.value and field.handleChange on the `` component.
• To show errors, add the aria-invalid prop to the component and the `data-invalid` prop to the component.

Component preview · Base UI
form-tanstack-input

Use the JGuang UI Registry URL provided on /systems/jguang-ui#install.

Textarea

• For textarea fields, use field.state.value and field.handleChange on the `` component.
• To show errors, add the aria-invalid prop to the component and the `data-invalid` prop to the component.

Component preview · Base UI
form-tanstack-textarea

<form.Field
  name="about"
  children={(field) => {
    const isInvalid = field.state.meta.isTouched && !field.state.meta.isValid
    return (
      <Field data-invalid={isInvalid}>
        <FieldLabel htmlFor="form-tanstack-textarea-about">
          More about you
        </FieldLabel>
        <Textarea
          id="form-tanstack-textarea-about"
          name={field.name}
          value={field.state.value}
          onBlur={field.handleBlur}
          onChange={(e) => field.handleChange(e.target.value)}
          aria-invalid={isInvalid}
          placeholder="I'm a software engineer..."
          className="min-h-[120px]"
        />
        <FieldDescription>
          Tell us more about yourself. This will be used to help us personalize
          your experience.
        </FieldDescription>
        {isInvalid && <FieldError errors={field.state.meta.errors} />}
      </Field>
    )
  }}
/>

Select

• For select components, use field.state.value and field.handleChange on the `` component.
• To show errors, add the aria-invalid prop to the component and the `data-invalid` prop to the component.

Component preview · Base UI
form-tanstack-select

<form.Field
  name="language"
  children={(field) => {
    const isInvalid = field.state.meta.isTouched && !field.state.meta.isValid
    return (
      <Field orientation="responsive" data-invalid={isInvalid}>
        <FieldContent>
          <FieldLabel htmlFor="form-tanstack-select-language">
            Spoken Language
          </FieldLabel>
          <FieldDescription>
            For best results, select the language you speak.
          </FieldDescription>
          {isInvalid && <FieldError errors={field.state.meta.errors} />}
        </FieldContent>
        <Select
          name={field.name}
          value={field.state.value}
          onValueChange={field.handleChange}
        >
          <SelectTrigger
            id="form-tanstack-select-language"
            aria-invalid={isInvalid}
            className="min-w-[120px]"
          >
            <SelectValue placeholder="Select" />
          </SelectTrigger>
          <SelectContent position="item-aligned">
            <SelectItem value="auto">Auto</SelectItem>
            <SelectItem value="en">English</SelectItem>
          </SelectContent>
        </Select>
      </Field>
    )
  }}
/>

Checkbox

• For checkbox, use field.state.value and field.handleChange on the `` component.
• To show errors, add the aria-invalid prop to the component and the `data-invalid` prop to the component.
• For checkbox arrays, use mode="array" on the <form.Field /> component and TanStack Form's array helpers.
• Remember to add data-slot="checkbox-group" to the `` component for proper styling and spacing.

Component preview · Base UI
form-tanstack-checkbox

<form.Field
  name="tasks"
  mode="array"
  children={(field) => {
    const isInvalid = field.state.meta.isTouched && !field.state.meta.isValid
    return (
      <FieldSet>
        <FieldLegend variant="label">Tasks</FieldLegend>
        <FieldDescription>
          Get notified when tasks you&apos;ve created have updates.
        </FieldDescription>
        <FieldGroup data-slot="checkbox-group">
          {tasks.map((task) => (
            <Field
              key={task.id}
              orientation="horizontal"
              data-invalid={isInvalid}
            >
              <Checkbox
                id={`form-tanstack-checkbox-${task.id}`}
                name={field.name}
                aria-invalid={isInvalid}
                checked={field.state.value.includes(task.id)}
                onCheckedChange={(checked) => {
                  if (checked) {
                    field.pushValue(task.id)
                  } else {
                    const index = field.state.value.indexOf(task.id)
                    if (index > -1) {
                      field.removeValue(index)
                    }
                  }
                }}
              />
              <FieldLabel
                htmlFor={`form-tanstack-checkbox-${task.id}`}
                className="font-normal"
              >
                {task.label}
              </FieldLabel>
            </Field>
          ))}
        </FieldGroup>
        {isInvalid && <FieldError errors={field.state.meta.errors} />}
      </FieldSet>
    )
  }}
/>

Radio Group

• For radio groups, use field.state.value and field.handleChange on the `` component.
• To show errors, add the aria-invalid prop to the component and the `data-invalid` prop to the component.

Component preview · Base UI
form-tanstack-radiogroup

<form.Field
  name="plan"
  children={(field) => {
    const isInvalid = field.state.meta.isTouched && !field.state.meta.isValid
    return (
      <FieldSet>
        <FieldLegend>Plan</FieldLegend>
        <FieldDescription>
          You can upgrade or downgrade your plan at any time.
        </FieldDescription>
        <RadioGroup
          name={field.name}
          value={field.state.value}
          onValueChange={field.handleChange}
        >
          {plans.map((plan) => (
            <FieldLabel
              key={plan.id}
              htmlFor={`form-tanstack-radiogroup-${plan.id}`}
            >
              <Field orientation="horizontal" data-invalid={isInvalid}>
                <FieldContent>
                  <FieldTitle>{plan.title}</FieldTitle>
                  <FieldDescription>{plan.description}</FieldDescription>
                </FieldContent>
                <RadioGroupItem
                  value={plan.id}
                  id={`form-tanstack-radiogroup-${plan.id}`}
                  aria-invalid={isInvalid}
                />
              </Field>
            </FieldLabel>
          ))}
        </RadioGroup>
        {isInvalid && <FieldError errors={field.state.meta.errors} />}
      </FieldSet>
    )
  }}
/>

Switch

• For switches, use field.state.value and field.handleChange on the `` component.
• To show errors, add the aria-invalid prop to the component and the `data-invalid` prop to the component.

Component preview · Base UI
form-tanstack-switch

<form.Field
  name="twoFactor"
  children={(field) => {
    const isInvalid = field.state.meta.isTouched && !field.state.meta.isValid
    return (
      <Field orientation="horizontal" data-invalid={isInvalid}>
        <FieldContent>
          <FieldLabel htmlFor="form-tanstack-switch-twoFactor">
            Multi-factor authentication
          </FieldLabel>
          <FieldDescription>
            Enable multi-factor authentication to secure your account.
          </FieldDescription>
          {isInvalid && <FieldError errors={field.state.meta.errors} />}
        </FieldContent>
        <Switch
          id="form-tanstack-switch-twoFactor"
          name={field.name}
          checked={field.state.value}
          onCheckedChange={field.handleChange}
          aria-invalid={isInvalid}
        />
      </Field>
    )
  }}
/>

Complex Forms

Here is an example of a more complex form with multiple fields and validation.

Component preview · Base UI
form-tanstack-complex

Resetting the Form

Use form.reset() to reset the form to its default values.

<Button type="button" variant="outline" onClick={() => form.reset()}>
  Reset
</Button>

Array Fields

TanStack Form provides powerful array field management with mode="array". This allows you to dynamically add, remove, and update array items with full validation support.

Component preview · Base UI
form-tanstack-array

This example demonstrates managing multiple email addresses with array fields. Users can add up to 5 email addresses, remove individual addresses, and each address is validated independently.

Array Field Structure

Use mode="array" on the parent field to enable array field management.

<form.Field
  name="emails"
  mode="array"
  children={(field) => {
    return (
      <FieldSet>
        <FieldLegend variant="label">Email Addresses</FieldLegend>
        <FieldDescription>
          Add up to 5 email addresses where we can contact you.
        </FieldDescription>
        <FieldGroup>
          {field.state.value.map((_, index) => (
            // Nested field for each array item
          ))}
        </FieldGroup>
      </FieldSet>
    )
  }}
/>

Nested Fields

Access individual array items using bracket notation: fieldName[index].propertyName. This example uses InputGroup to display the remove button inline with the input.

<form.Field
  name={`emails[${index}].address`}
  children={(subField) => {
    const isSubFieldInvalid =
      subField.state.meta.isTouched && !subField.state.meta.isValid
    return (
      <Field orientation="horizontal" data-invalid={isSubFieldInvalid}>
        <FieldContent>
          <InputGroup>
            <InputGroupInput
              id={`form-tanstack-array-email-${index}`}
              name={subField.name}
              value={subField.state.value}
              onBlur={subField.handleBlur}
              onChange={(e) => subField.handleChange(e.target.value)}
              aria-invalid={isSubFieldInvalid}
              placeholder="name@example.com"
              type="email"
            />
            {field.state.value.length > 1 && (
              <InputGroupAddon align="inline-end">
                <InputGroupButton
                  type="button"
                  variant="ghost"
                  size="icon-xs"
                  onClick={() => field.removeValue(index)}
                  aria-label={`Remove email ${index + 1}`}
                >
                  <XIcon />
                </InputGroupButton>
              </InputGroupAddon>
            )}
          </InputGroup>
          {isSubFieldInvalid && (
            <FieldError errors={subField.state.meta.errors} />
          )}
        </FieldContent>
      </Field>
    )
  }}
/>

Adding Items

Use field.pushValue(item) to add items to an array field. You can disable the button when the array reaches its maximum length.

<Button
  type="button"
  variant="outline"
  size="sm"
  onClick={() => field.pushValue({ address: "" })}
  disabled={field.state.value.length >= 5}
>
  Add Email Address
</Button>

Removing Items

Use field.removeValue(index) to remove items from an array field. You can conditionally show the remove button only when there's more than one item.

{
  field.state.value.length > 1 && (
    <InputGroupButton
      onClick={() => field.removeValue(index)}
      aria-label={`Remove email ${index + 1}`}
    >
      <XIcon />
    </InputGroupButton>
  )
}

Array Validation

Validate array fields using Zod's array methods.

const formSchema = z.object({
  emails: z
    .array(
      z.object({
        address: z.string().email("Enter a valid email address."),
      })
    )
    .min(1, "Add at least one email address.")
    .max(5, "You can add up to 5 email addresses."),
})