What is the regex for us routing number?

The regex pattern for us routing number is `^\d{9}$`. This pattern validates us bank routing number (aba) — exactly 9 digits.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^\d{9}$/;` 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'^\d{9}$', 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 (`/^\d{9}$/i`) or use `re.IGNORECASE` in Python.

Regex for US Routing Number

Regex Pattern

^\d{9}$

US bank routing number (ABA) — exactly 9 digits

Quick Answer

The regex pattern for us routing number is `^\d{9}$`. US bank routing number (ABA) — exactly 9 digits. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
021000021	✓ Matches
121042882	✓ Matches
011401533	✓ Matches
12345678	✗ No match
1234567890	✗ No match
ABCDEFGHI	✗ No match

Code Examples

javascript

const regex = /^\d{9}$/;
const isValid = regex.test(value);

python

import re
pattern = r'^\d{9}$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^\d{9}$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^\d{9}$/', $value)) {
    echo "valid";
}

java

String pattern = "^\\d{9}$";
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

American Express Card

Amex — 15 digits starting with 34 or 37

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