validatorjs/validator.js · error · Error

${provider} is not a valid credit card provider.

Error message

${provider} is not a valid credit card provider.

What it means

isCreditCard(str, provider) optionally restricts validation to one card provider ('amex', 'dinersclub', 'discover', 'jcb', 'mastercard', 'unionpay', 'visa', 'mir', 'elo', 'hipercard'). Passing any other truthy provider string throws this error because the library cannot restrict to an unknown brand.

Source

Thrown at src/lib/isCreditCard.js:36

    if (cards.hasOwnProperty(cardProvider)) {
      tmpCardsArray.push(cards[cardProvider]);
    }
  }
  return tmpCardsArray;
})();

export default function isCreditCard(card, options = {}) {
  assertString(card);
  const { provider } = options;
  const sanitized = card.replace(/[- ]+/g, '');
  if (provider && provider.toLowerCase() in cards) {
    // specific provider in the list
    if (!(cards[provider.toLowerCase()].test(sanitized))) {
      return false;
    }
  } else if (provider && !(provider.toLowerCase() in cards)) {
    /* specific provider not in the list */
    throw new Error(`${provider} is not a valid credit card provider.`);
  } else if (!allCards.some(cardProvider => cardProvider.test(sanitized))) {
    // no specific provider
    return false;
  }
  return isLuhnValid(card);
}

View on GitHub (pinned to a79ff980ab)

Solutions

1. Use one of the exact supported keys (lowercase, no spaces): amex, dinersclub, discover, jcb, mastercard, unionpay, visa, mir, elo, hipercard
2. Normalize/trim your provider string before calling
3. If the brand is not supported, call without a provider to validate against all cards
4. Check the current cards table in src/lib/isCreditCard.js for the supported set in your version

Example fix

// before
validator.isCreditCard(num, 'Master Card'); // throws
// after
validator.isCreditCard(num, 'mastercard');

const CARDS = ['amex','dinersclub','discover','jcb','mastercard','unionpay','visa','mir','elo','hipercard'];
const providerOk = (p) => !p || CARDS.includes(String(p).toLowerCase().trim());
if (!providerOk(provider)) throw new TypeError(`Unsupported provider: ${provider}`);

const isCardProvider = (p) => typeof p === 'string' && CARDS.includes(p.toLowerCase().trim());

let ok;
try { ok = validator.isCreditCard(num, provider); }
catch (e) { if (/not a valid credit card provider/.test(e.message)) { ok = validator.isCreditCard(num); } else { throw e; } }

When it happens

Trigger: isCreditCard('4111...', 'Visa Card') (name not an exact key), isCreditCard(num, 'MASTERCARD ')? with stray whitespace/typo like 'master card' or 'maestro', or a provider value read from user config.

Common situations: Free-form brand names from a database or API ('VISA credit') instead of the exact enum keys; assuming 'maestro' or 'rupay' are supported; case handled by the library but spelling must match the key exactly.

Related errors

• ignore should be instance of a String or RegExp
• Invalid locale '${locale}'
• ignore should be instance of a String or RegExp
• Invalid locale '${locale}'
• Invalid locale '${options.locale}'

AI-assisted analysis of validatorjs/validator.js@a79ff980ab (2026-08-31). Data as JSON: /api/errors/8b458c7231a09a09. Report an issue: GitHub.