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BIN / IIN inspector

The first 6–8 digits of a card number are its BIN (Bank Identification Number, also called the IIN). They identify the scheme and the rules a valid number follows: its allowed lengths and CVV length. Paste a test number or just the leading digits to inspect it. This is a structural check for QA work; it does not tell you whether a card is real, active, or has funds.

Runs entirely in your browser. Nothing is sent to a server. Scheme, valid lengths, and CVV length are computed from the IIN; issuer, type, and country are enriched from a small CC-BY sample of well-known prefixes, not a comprehensive BIN database.

Browse the bundled BIN sample (14)show
BINSchemeIssuerCountry
424242VisaStripe testUS
400005VisaStripe testUS
555555MastercardStripe testUS
222300MastercardStripe testUS
520082MastercardStripe testUS
510510MastercardStripe testUS
378282American ExpressAmex testUS
601111DiscoverDiscover testUS
356600JCBJCB testJP
305693Diners ClubDiners testUS
620000UnionPayUnionPay testCN
414720VisaChaseUS
542418MastercardBarclaysGB
455673VisaBank of AmericaUS

What the inspector reports

The bundled data is a small illustrative sample, not a comprehensive BIN database. That’s a data-maintenance trap and a fraud-adjacent use we don’t serve. It exists so you can wire BIN detection into your own test suites. The hosted /api/v1/bin endpoint covers more prefixes.

Use the BIN API in your tests

Need this in CI or a script? The same lookup is one GET request away. Authenticate with a free key via ?key= or an Authorization: Bearer header. Get a free key →

curl "https://www.testcards.io/api/v1/bin?bin=424242&key=YOUR_KEY"

# Or send the key as a Bearer token instead of ?key=
curl -H "Authorization: Bearer YOUR_KEY" \
  "https://www.testcards.io/api/v1/bin?bin=424242"