Validators

svelte-tel-input ships a separate subpath export for form validation — zero impact on your bundle if you don’t use it.

import { validateTelInput } from 'svelte-tel-input/validators';

validateTelInput()

validateTelInput(
  value: string,
  options?: TelValidatorOptions
): ValidationError

Returns a ValidationError (null when valid). Works with any schema library.

Options

interface TelValidatorOptions {
  required?: boolean;              // default: false
  allowedCountries?: CountryCode[];
  country?: CountryCode | null;   // hint for numbers without '+'
}

Framework examples

Zod

import { z } from 'zod';
import { validateTelInput } from 'svelte-tel-input/validators';

const schema = z.object({
  phone: z.string().superRefine((val, ctx) => {
    const error = validateTelInput(val, { required: true });
    if (error) {
      ctx.addIssue({ code: 'custom', message: error });
    }
  })
});

schema.parse({ phone: '+36301234567' }); // ✓
schema.parse({ phone: '' });             // ✗ 'REQUIRED'
schema.parse({ phone: '+1999' });        // ✗ 'TOO_SHORT'

Valibot

import * as v from 'valibot';
import { validateTelInput } from 'svelte-tel-input/validators';

const schema = v.object({
  phone: v.pipe(
    v.string(),
    v.check(
      (val) => !validateTelInput(val, { required: true }),
      'Invalid phone number'
    )
  )
});

Yup

import * as yup from 'yup';
import { validateTelInput } from 'svelte-tel-input/validators';

const schema = yup.object({
  phone: yup.string().test(
    'tel',
    'Invalid phone number',
    (val) => !validateTelInput(val ?? '', { required: true })
  )
});

Allowed countries

Restrict to a subset of countries:

const error = validateTelInput('+442012345678', {
  allowedCountries: ['US', 'HU']
});
// 'COUNTRY_NOT_ALLOWED' — GB is not in the list

Country hint

When validating numbers without a + prefix, pass a country hint:

validateTelInput('301234567', { country: 'HU' });    // null (valid)
validateTelInput('301234567');                         // 'INVALID' (no country context)

Return values

validateTelInput returns one of the ValidationError values:

Return	Meaning
null	Valid
'REQUIRED'	Empty value with required: true
'TOO_SHORT'	Not enough digits
'TOO_LONG'	Too many digits
'NOT_A_NUMBER'	Doesn’t look like a phone number
'INVALID_COUNTRY'	Unrecognized country code
'INVALID_LENGTH'	Length doesn’t match any valid pattern
'COUNTRY_NOT_ALLOWED'	Valid number but country not in allowedCountries
'INVALID'	Fallback