Card BIN Validator

Card BIN/IIN: the opening digits that name the brand and issuer

The BIN (Bank Identification Number), now formally the IIN (Issuer Identification Number), is the opening digits of a card number that identify the card brand and the issuing bank. Defined by ISO/IEC 7812, it was historically the first 6 digits and was extended to 8 digits from 2022. This tool reads the prefix and reports the likely brand and type (credit/debit).

The very first digit is the MII (Major Industry Identifier): 4 = Visa, 5/2 = Mastercard, 3 = Amex/Diners/JCB, 6 = Discover/Elo. The brand-specific ranges follow from there.

Brand prefixes

• Visa: starts with 4.
• Mastercard: 51–55 and the newer 2221–2720 range.
• Amex: 34 / 37 · Diners: 36, 38, 300–305.
• Brazilian brands: Elo and Hipercard use specific multi-digit ranges (e.g. Hipercard 606282).

BIN vs the whole card number

• BIN identifies the brand/issuer; the full number additionally passes the Luhn check digit.
• Routing & fraud: acquirers route and risk-score by BIN before authorisation.
• Debit vs credit: some BIN ranges signal product type, affecting fees and rules.
• Co-badged cards: a card may carry two brands; the BIN reflects one network.

Common pitfalls

• BIN ≠ validity: a recognised prefix says nothing about whether the card is active, funded or stolen.
• 6 → 8 digit shift: legacy 6-digit BIN tables miss issuers that share a 6-digit prefix; use 8-digit data.
• Never store full PANs: PCI-DSS restricts handling card numbers — use the BIN for routing, not storage of the whole number.
• Prefix overlap: some ranges are reassigned or shared; treat brand detection as best-effort.

FAQ

How many digits is a BIN now? ISO/IEC 7812 extended the IIN to 8 digits in 2022; older systems still use 6.

Does the BIN tell me if a card is valid? No — it identifies brand/issuer only. The Luhn digit checks the number's integrity; only the issuer confirms it's active.

What does the first digit mean? It's the Major Industry Identifier — 4 Visa, 5/2 Mastercard, 3 Amex/Diners, 6 Discover/Elo.