Validation reference

Rule syntaxes

A rule returns true, a message string, an array of messages (since 4.10.0), or a promise of either (GenericValidateFunction, dist/vee-validate.d.ts:318). Validators receive (value, ctx) where ctx is FieldValidationMetaInfo with field, name, label, value, form (dist/vee-validate.d.ts:157-167) — use ctx.form for cross-field validation.

const isStrong = (value: string) =>
  value.length >= 8 || 'Use at least 8 characters';

const { defineField } = useForm({
  validationSchema: {
    password: [isStrong, mustContainDigit], // array of validators runs in order, bails by default
  },
});

Object schemas

Object schemas map field paths to rules, strings (global rule syntax), or nested objects. Field-level with useField: pass the rule expression directly. Form-level paths support dot and bracket notation (RawFormSchema, dist/vee-validate.d.ts:359).

Typed schemas (yup, zod, valibot)

Wrap third-party schemas with toTypedSchema from the matching adapter package, then pass to validationSchema. InferOutput/InferInput differentiate the submitted type from the form type (dist/vee-validate.d.ts:200-201), useful for schemas that transform values (e.g. zod coercion, z.coerce.number()).

import { toTypedSchema } from '@vee-validate/zod';
import * as z from 'zod';

const schema = toTypedSchema(
  z.object({
    email: z.string().email(),
    age: z.coerce.number().min(18),
  })
);

const { handleSubmit } = useForm({ validationSchema: schema });

Passing a raw yup/zod schema without toTypedSchema produces "No such validator 'VVTypedSchema' exists" (https://github.com/logaretm/vee-validate/discussions/4819). Schema casts apply on submit and on resetForm (since 4.10.6). Sources: https://vee-validate.logaretm.com/v4/guide/composition-api/typed-schema/, https://vee-validate.logaretm.com/v4/integrations/zod-schema-validation/

Zod 4 requires @vee-validate/zod >= 4.15.0 (https://github.com/logaretm/vee-validate/issues/5027).

Global validators (legacy, string rules)

defineRule(id, validator) registers string rules usable as 'required|email' or { required: true, min: 2 } (dist/vee-validate.d.ts:504). The @vee-validate/rules package ships 25+ rules; @vee-validate/i18n ships 45+ locales (README:50-51). Global rules need a message source: configure({ generateMessage }) or the i18n package (https://vee-validate.logaretm.com/v4/guide/global-validators/, https://vee-validate.logaretm.com/v4/guide/i18n/).

String rules work without any of this when every rule is a function; the typed/composition path is preferred for new code.

Global configuration

import { configure } from 'vee-validate';

configure({
  bails: true,                  // stop on first failing rule (per validator array; yup unaffected)
  validateOnBlur: true,
  validateOnChange: true,
  validateOnInput: false,
  validateOnModelUpdate: true,
  generateMessage: ctx => `${ctx.field} is invalid`,
});

VeeValidateConfig at dist/vee-validate.d.ts:506-514. The four validateOn* flags only affect <Field> components, not useField (https://vee-validate.logaretm.com/v4/api/configuration/).

Standalone validation utils

validate(value, rules, options?): validate a single value outside any form (dist/vee-validate.d.ts:492).
validateObject(schema, values): validate an object against a form schema (dist/vee-validate.d.ts:493-499).
normalizeRules, isNotNestedPath, cleanupNonNestedPath: path and rule helpers (dist/vee-validate.d.ts:519-526).

Async validation

Return a promise from a validator. meta.pending (field) and isValidating (form, since 4.9.3) track in-flight validation. To avoid flicker, disable submit on isSubmitting || isValidating (https://vee-validate.logaretm.com/v4/examples/async-validation).

/vee-validate-skilld

referencesvalidation.md