What is the regex for american express card?

The regex pattern for american express card is `^3[47][0-9]{13}$`. This pattern validates amex — 15 digits starting with 34 or 37.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^3[47][0-9]{13}$/;` and test with `regex.test(yourValue)`. It returns `true` if the value matches.

How do I use this regex in Python?

In Python, use `import re; re.match(r'^3[47][0-9]{13}$', value)`. The raw string prefix (`r`) prevents Python from interpreting backslashes as escape characters.

Is this regex case-sensitive?

By default, yes. To make it case-insensitive, add the `i` flag in JavaScript (`/^3[47][0-9]{13}$/i`) or use `re.IGNORECASE` in Python.

Regex for American Express Card

Regex Pattern

^3[47][0-9]{13}$

Amex — 15 digits starting with 34 or 37

Quick Answer

The regex pattern for american express card is `^3[47][0-9]{13}$`. Amex — 15 digits starting with 34 or 37. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
378282246310005	✓ Matches
371449635398431	✓ Matches
4111111111111111	✗ No match
3782822463100	✗ No match
3512345678901234	✗ No match

Code Examples

javascript

const regex = /^3[47][0-9]{13}$/;
const isValid = regex.test(value);

python

import re
pattern = r'^3[47][0-9]{13}$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^3[47][0-9]{13}$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^3[47][0-9]{13}$/', $value)) {
    echo "valid";
}

java

String pattern = "^3[47][0-9]{13}$";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

Related Regex Patterns

Visa Credit Card

Visa card — starts with 4, 13 or 16 digits total

Mastercard Credit Card

Mastercard — 16 digits starting with 51-55 or 2221-2720

Any Credit Card

Visa, Mastercard, Amex, Discover, Diners

Discover Credit Card

Discover card — starts with 6011 or 65, 16 digits total

Diners Club Credit Card

Diners Club card — starts with 300-305, 36, or 38, 14 digits total

JCB Credit Card

JCB card — starts with 3528-3589, 16 digits total