Max Length

Validates that a string is at most a given number of characters long.

Configuration

Config flag	Type	Description
`maxLength`	`number`	Maximum number of characters.
`maxLength`	`[number, string]`	Tuple form — the length plus a custom message.

const form = useForm({
  initialValues: { bio: '' },
  validationSchema: {
    bio: { maxLength: 160 },
  },
});

With a custom message:

bio: { maxLength: [160, 'At most {max} characters'] }

import { V } from 'formify-js';

V.maxLength(160);

Scenario	Message
Value is longer than the maximum	`Must be at most 160 characters` (the number reflects your value)

Value	Rule	Result
`'abc'`	`maxLength: 3`	✅ Valid
`'abcd'`	`maxLength: 3`	❌ Invalid

The check is inclusive: a value of exactly 3 characters passes maxLength: 3.
Combine with minLength to define an exact allowed range.