Twilio Auth Token / SID Regex for Python

What this pattern does

This page provides a well-structured, multi-part regular expression for matching twilio auth token / sid, ported and verified for Python. 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 Python project — whether you're validating in a Django view, a FastAPI endpoint, or a standalone data processing script.

Python Implementation

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

import re

twilio_auth_token_sid_pattern = re.compile(r'^(AC[a-z0-9]{32}|SK[a-z0-9]{32}|[a-f0-9]{32})$')

def validate_twilio_auth_token_sid(value: str) -> bool:
    return bool(twilio_auth_token_sid_pattern.fullmatch(value))

# Example
print(validate_twilio_auth_token_sid("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 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

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.