Semantic Version with 'v' Prefix Regex for JavaScript

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching semantic version with 'v' prefix, ported and verified for JavaScript. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your JavaScript project — whether you're validating in an Express middleware, a Next.js API route, or a client-side form.

Javascript Implementation

// Semantic Version with 'v' Prefix
// ReDoS-safe | RegexVault — Dev & Systems > SemVer

const semanticVersionWithVPrefixRegex = /^[vV]?(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)(?:-((?:0|[1-9][0-9]*|[0-9]*[a-zA-Z\-][a-zA-Z0-9\-]*)(?:\.(?:0|[1-9][0-9]*|[0-9]*[a-zA-Z\-][a-zA-Z0-9\-]*))*))?(?:\+([a-zA-Z0-9\-]+(?:\.[a-zA-Z0-9\-]+)*))?$/;

function validateSemanticVersionWithVPrefix(input: string): boolean {
  return semanticVersionWithVPrefixRegex.test(input);
}

// Example
console.log(validateSemanticVersionWithVPrefix("v1.0.0")); // true

Test Cases

When to use this pattern

This pattern is drawn from the Dev & Systems > SemVer category and carries a ReDoS-safe certification. That matters for JavaScript developers because especially critical in long-running Node.js event loops where a ReDoS vulnerability can block the entire process. 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

The v prefix is a convention in Git tagging but not part of SemVer 2.0.0 spec. Strip the v before semantic comparison. Go modules use v+SemVer as their module versioning scheme.