What is the regex for ethereum address?

The regex pattern for ethereum address is `^0x[0-9a-fA-F]{40}$`. This pattern validates ethereum address — 0x prefix followed by 40 hex characters.

How do I use this regex in JavaScript?

In JavaScript, create the regex with `const regex = /^0x[0-9a-fA-F]{40}$/;` 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'^0x[0-9a-fA-F]{40}$', 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 (`/^0x[0-9a-fA-F]{40}$/i`) or use `re.IGNORECASE` in Python.

Regex for Ethereum Address

Regex Pattern

^0x[0-9a-fA-F]{40}$

Ethereum address — 0x prefix followed by 40 hex characters

Quick Answer

The regex pattern for ethereum address is `^0x[0-9a-fA-F]{40}$`. Ethereum address — 0x prefix followed by 40 hex characters. This works in JavaScript, Python, Ruby, PHP, Java, and most regex engines that support PCRE syntax.

Test Examples

Input	Result
0x742d35Cc6634C0532925a3b844Bc9e7595f2bD18	✓ Matches
0x0000000000000000000000000000000000000000	✓ Matches
742d35Cc6634C0532925a3b844Bc9e7595f2bD18	✗ No match
0x742d35Cc	✗ No match
0xGGGGGG	✗ No match

Code Examples

javascript

const regex = /^0x[0-9a-fA-F]{40}$/;
const isValid = regex.test(value);

python

import re
pattern = r'^0x[0-9a-fA-F]{40}$'
if re.match(pattern, value):
    print("valid")

ruby

pattern = /^0x[0-9a-fA-F]{40}$/
if value =~ pattern
  puts "valid"
end

php

if (preg_match('/^0x[0-9a-fA-F]{40}$/', $value)) {
    echo "valid";
}

java

String pattern = "^0x[0-9a-fA-F]{40}$";
boolean isValid = value.matches(pattern);

Frequently Asked Questions

Related Regex Patterns

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Mastercard Credit Card

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American Express Card

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Visa, Mastercard, Amex, Discover, Diners

Discover Credit Card

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

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