UUID Regex Python Validator

What is UUID Regex?

A UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely label data across systems. It’s typically represented as 32 hexadecimal characters split into 5 groups by hyphens, like:

123e4567-e89b-12d3-a456-426614174000

UUIDs are used in databases, APIs, microservices, IoT, and any context requiring global uniqueness.

UUID Regex Pattern in Python

To match a standard UUID format (v1–v5), use this regex pattern:

^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-5][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}$

This pattern checks:

• 8 hexadecimal characters

• 4-digit version group (starting with 1–5)

• 4-digit variant group (starting with 8–b)

• Final 12 hex digits

How to Validate UUIDs Using Regex in Python

Here’s how to use the re module in Python to match valid UUIDs:

import re

def is_valid_uuid(uuid_str):
    pattern = re.compile(r'^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-5][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}$')
    return bool(pattern.match(uuid_str))

# Example test
uuids = [
    "123e4567-e89b-12d3-a456-426614174000",  # Valid
    "123e4567e89b12d3a456426614174000",      # Invalid (no hyphens)
    "ZZZe4567-e89b-12d3-a456-426614174000"   # Invalid (non-hex)
]

for u in uuids:
    print(f"{u} -> {is_valid_uuid(u)}")

Use Cases

• API Resource Identification: Use UUIDs in REST endpoints or JSON payloads to reference records uniquely.

• Database Indexing: Use UUIDs as primary keys to prevent collision across distributed tables.

• Session Management: Validate UUID-based tokens for user sessions in secure applications.

• Form Submissions: Check if hidden fields in forms pass valid UUIDs.

• Combine with Password Regex Python Validator to secure user login data.

Pro Tips

• UUIDs can be lowercase or uppercase, and this pattern matches both.

• Use Python’s uuid module to generate and compare UUIDs, and validate format with this regex.

• This regex only checks the format, not the UUID’s randomness or version logic.

• Normalize UUIDs to lowercase using .lower() before storage for consistency.

• Combine with the Email Regex Python Validator or Phone Number Regex Python Validator for full form validation in Python apps.