Bitcoin Address (P2SH — starts with 3) Regex for Java

What this pattern does

This page provides a well-structured, multi-part regular expression for matching bitcoin address (p2sh — starts with 3), ported and verified for Java. 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 Java project — whether you're validating in a Spring Boot controller, a Jakarta EE service, or a standalone utility class.

Java Implementation

// Bitcoin Address (P2SH — starts with 3)
// ReDoS-safe | RegexVault — Finance > Crypto

import java.util.regex.Pattern;

public class BitcoinAddressP2shStartsWith3Validator {
    private static final Pattern PATTERN =
        Pattern.compile("^3[a-km-zA-HJ-NP-Z1-9]{25,34}$");

    public static boolean validate(String input) {
        return PATTERN.matcher(input).matches();
    }

    // Example
    public static void main(String[] args) {
        System.out.println(validate("3J98t1WpEZ73CNmQviecrnyiWrnqRhWNLy")); // 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 Java developers because critical in Java applications since the JVM regex engine uses backtracking and is susceptible to ReDoS without careful pattern design. 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

P2SH addresses start with 3. Commonly used for multisignature wallets and wrapped SegWit (P2SH-P2WPKH). More flexible than P2PKH — can represent complex spending conditions.