UUID Generator

About UUID Generator

UUIDTools.com provides a free API for generating UUIDs and GUIDs for testing purposes, with no authentication required. It supports version-1, version-3, version-4, version-5, and "timestamp-first" UUID generation, as well as a decode endpoint that identifies the version and content of a given UUID. Version-1 and version-4 UUIDs are randomly generated (version-1 incorporating time-based data), while version-3 and version-5 UUIDs are deterministic, computed from a namespace and name using MD5 and SHA-1 hashing respectively; the "name" parameter can also be base64-encoded. Timestamp-first UUIDs embed the creation timestamp at the start of the value so that records sort chronologically when stored in a database index.

Endpoints that accept a count parameter allow generating up to 100 UUIDs in a single request, except for the deterministic version-3 and version-5 endpoints, which only return one UUID per request since identical inputs always produce identical outputs. All endpoints are rate-limited to 60 requests per minute per IP address, and the API supports CORS for use directly from client-side websites.

This tool is suited for developers who need to generate or inspect UUIDs during testing, prototyping, or database design, including use cases involving ordered identifiers for indexed storage.

Key features

• Generate version-1, version-3, version-4, version-5, and timestamp-first UUIDs via REST API
• Generate up to 100 UUIDs per request
• Decode a UUID to reveal its version, variant, and embedded metadata
• Deterministic UUID generation (v3/v5) from a namespace and name, with base64-encoded name support
• CORS-enabled for direct use from browser-based websites
• No authentication required

Frequently asked questions