Credit Card Type Detector
Detect a card network — Visa, Mastercard, Amex, Discover, and more — from its number prefix.
Nothing you type here is sent to a server or stored anywhere — detection runs entirely in your browser from published prefix ranges, and doesn't validate that the number is real.
Detected network
Visa
For informational and educational purposes only — not professional or technical advice, and not a substitute for consulting a qualified professional about your specific situation. TrueMeasureKit is not liable for decisions made based on these results. See our Terms of Service.
How network detection works from just a few digits
Card networks are assigned specific leading-digit ranges by ISO/IEC 7812 (the same standard behind BIN/IIN lookups) — Visa numbers always start with 4, Amex with 34 or 37, and so on. That's enough to identify the network before a single digit of the actual account number is known, which is why checkout forms can show a Visa or Mastercard icon the moment you start typing, well before the full card number — or its checksum — has been entered.
Frequently asked questions
How is the card network identified from just the number?
Card networks are assigned specific leading digit ranges (called IIN/BIN ranges) — Visa numbers start with 4, Mastercard with 51-55 or 2221-2720, Amex with 34 or 37, and so on — detection just matches the prefix against known ranges.