Ethereum Address Regex for Python

What this pattern does

This page provides a lightweight, single-purpose regular expression for matching ethereum address, ported and verified for Python. Financial data validation has zero tolerance for false negatives — a missed invalid entry can corrupt downstream calculations. The snippet below is ready to drop into your Python project — whether you're validating in a Django view, a FastAPI endpoint, or a standalone data processing script.

Python Implementation

# Ethereum Address
# ReDoS-safe | RegexVault — Finance > Crypto

import re

ethereum_address_pattern = re.compile(r'^0x[0-9a-fA-F]{40}$')

def validate_ethereum_address(value: str) -> bool:
    return bool(ethereum_address_pattern.fullmatch(value))

# Example
print(validate_ethereum_address("0x742d35Cc6634C0532925a3b844Bc454e4438f44e"))  # True

Test Cases

When to use this pattern

This pattern is drawn from the Finance > Crypto category and carries a ReDoS-safe certification. That matters for Python developers because particularly important in Python web servers where CPU-bound regex operations can stall concurrent request handling. 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

Case-insensitive for format validation. EIP-55 checksum encoding uses mixed case — 0xAb8483... is a checksummed address. Validate checksum with web3.utils.isAddress() or ethers.js utils.getAddress().