Form schema validation

Schema-based validation

@mantine/form has built-in support for Standard Schema – a community specification implemented by many popular schema validation libraries including zod, valibot, and arktype. Use schemaResolver to validate forms with any Standard Schema-compliant library without extra resolver packages.

Full list of supported libraries

If you do not know which schema validation library to choose, use zod – it is the most modern and developer-friendly library.

Sync and async schemas

By default, schemaResolver returns a function that may return a Promise, since the Standard Schema specification allows async validation. Pass { sync: true } when you know your schema is synchronous (e.g., Zod, Valibot) to get synchronous return types for form.validate(), form.validateField(), and form.isValid().

zod

Installation:

yarn add zod

Basic field validation:

import { z } from 'zod/v4';
import { useForm, schemaResolver } from '@mantine/form';

const schema = z.object({
  name: z.string().min(2, { error: 'Name should have at least 2 letters' }),
  email: z.email({ error: 'Invalid email' }),
  age: z.number().min(18, { error: 'You must be at least 18 to create an account' }),
});

const form = useForm({
  mode: 'uncontrolled',
  initialValues: {
    name: '',
    email: '',
    age: 16,
  },
  validate: schemaResolver(schema, { sync: true }),
});

form.validate();
form.errors;
// -> {
//  name: 'Name should have at least 2 letters',
//  email: 'Invalid email',
//  age: 'You must be at least 18 to create an account'
// }

Nested field validation:

import { z } from 'zod/v4';
import { useForm, schemaResolver } from '@mantine/form';

const nestedSchema = z.object({
  nested: z.object({
    field: z.string().min(2, { error: 'Field should have at least 2 letters' }),
  }),
});

const form = useForm({
  mode: 'uncontrolled',
  initialValues: {
    nested: {
      field: '',
    },
  },
  validate: schemaResolver(nestedSchema, { sync: true }),
});

form.validate();
form.errors;
// -> {
//  'nested.field': 'Field should have at least 2 letters',
// }

List field validation:

import { z } from 'zod/v4';
import { useForm, schemaResolver } from '@mantine/form';

const listSchema = z.object({
  list: z.array(
    z.object({
      name: z.string().min(2, { error: 'Name should have at least 2 letters' }),
    })
  ),
});

const form = useForm({
  mode: 'uncontrolled',
  initialValues: {
    list: [{ name: '' }],
  },
  validate: schemaResolver(listSchema, { sync: true }),
});

form.validate();
form.errors;
// -> {
//  'list.0.name': 'Name should have at least 2 letters',
// }

Async validation – use schemaResolver without { sync: true } when your schema includes async checks (e.g., checking if an email is already taken via an API call). In this case, form.validate(), form.validateField(), and form.isValid() return promises:

import { z } from 'zod/v4';
import { useForm, schemaResolver } from '@mantine/form';

const schema = z
  .object({
    email: z.email({ error: 'Invalid email' }),
  })
  .refine(
    async (data) => {
      const isTaken = await checkEmailExists(data.email);
      return !isTaken;
    },
    { error: 'Email is already taken', path: ['email'] }
  );

const form = useForm({
  mode: 'uncontrolled',
  initialValues: { email: '' },
  validate: schemaResolver(schema),
});

// form.validate() returns a Promise
await form.validate();

Form validation

Form validators