Credit Card Number with Network Detection Regex for Go

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching credit card number with network detection, ported and verified for Go. Identity and credential patterns need both correctness and safety, since they're frequent targets for adversarial input. The snippet below is ready to drop into your Go project — whether you're validating in a Gin handler, a gRPC service, or a command-line tool.

Go Implementation

// Credit Card Number with Network Detection
// ReDoS-safe | RegexVault — Identity & PII > Financial PII

package validation

import "regexp"

var creditCardNumberWithNetworkDetectionRe = regexp.MustCompile(`^(?:(4)[0-9]{12}(?:[0-9]{3,6})?|(5[1-5][0-9]{14}|2(?:2[2-9][1-9]|[3-6][0-9]{2}|7[01][0-9]|720)[0-9]{12})|(3[47][0-9]{13})|(3(?:0[0-5]|[68][0-9])[0-9]{11})|(6(?:011|5[0-9]{2})[0-9]{12,15})|((?:2131|1800|35[0-9]{3})[0-9]{11}))$`)

func ValidateCreditCardNumberWithNetworkDetection(s string) bool {
    return creditCardNumberWithNetworkDetectionRe.MatchString(s)
}

// Example
// fmt.Println(ValidateCreditCardNumberWithNetworkDetection("4111111111111111")) // true

Test Cases

When to use this pattern

This pattern is drawn from the Identity & PII > Financial PII category and carries a ReDoS-safe certification. That matters for Go developers because Go's RE2 engine is inherently safe from catastrophic backtracking, but this pattern has been additionally verified for correctness. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.

Common Pitfalls

Technical Notes

Capture groups: 1=Visa, 2=Mastercard, 3=Amex, 4=Diners Club, 5=Discover, 6=JCB. PCI-DSS: never store CVV, never log PANs, always encrypt stored card data, use tokenization for recurring billing.