Twilio Auth Token / SID Regex for JavaScript

What this pattern does

This page provides a well-structured, multi-part regular expression for matching twilio auth token / sid, ported and verified for JavaScript. In security-sensitive code, using an unverified regex can open the door to both false positives and denial-of-service attacks. 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

// Twilio Auth Token / SID
// ReDoS-safe | RegexVault — Security > API Keys & Tokens

const twilioAuthTokenSidRegex = /^(AC[a-z0-9]{32}|SK[a-z0-9]{32}|[a-f0-9]{32})$/i;

function validateTwilioAuthTokenSid(input: string): boolean {
  return twilioAuthTokenSidRegex.test(input);
}

// Example
console.log(validateTwilioAuthTokenSid("ACa1b2c3d4e5f6a1b2c3d4e5f6a1b2c3d4")); // true

Test Cases

When to use this pattern

This pattern is drawn from the Security > API Keys & Tokens 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

Twilio Account SID: AC + 32 hex chars. Auth Token: 32 hex chars (no prefix). API Key SID: SK + 32 hex chars. Auth Tokens have full account access. API Keys can be scoped and are preferred over Auth Tokens.