What is UUID Generator?
The UUID Generator creates universally unique identifiers (UUIDs) conforming to RFC 9562 (formerly RFC 4122). UUIDs are 128-bit identifiers represented as 32 hexadecimal digits in a 8-4-4-4-12 format (e.g., 550e8400-e29b-41d4-a716-446655440000). They are the standard solution for generating unique identifiers without a central authority — essential for distributed systems, databases, APIs, and any application where collisions between independently generated IDs must be virtually impossible. This tool supports Version 1 (timestamp + node-based), Version 4 (purely random, the most widely used), and Version 7 (Unix-timestamp-ordered random, ideal for databases), letting you pick the version best suited to your use case.
Why Use UUID Generator?
Developers need UUIDs constantly: as database primary keys, API idempotency keys, session identifiers, file names, correlation IDs in microservices, and more. Generating them via command-line scripts or language-specific libraries works but adds friction when you just need a quick ID to paste into a config file, seed a database, or test an API endpoint. This tool provides instant generation of one or hundreds of UUIDs with a single click. It also explains the structure of each UUID — showing the version bits, variant bits, and embedded timestamp (for v1 and v7) — which is valuable for understanding what information a UUID encodes and choosing the right version.
How to Use
Select the UUID version you want: v1 (timestamp-based), v4 (random), or v7 (timestamp-ordered random). Set the quantity (1 to 1,000 UUIDs) and formatting options: uppercase or lowercase, with or without hyphens, with or without surrounding braces (for GUID format). Click 'Generate' to produce the UUIDs. Each UUID is displayed in a list that you can copy individually or copy all at once. For v1 and v7 UUIDs, hover over a UUID to see the decoded timestamp. Use the 'Validate' tab to paste an existing UUID and check its version, variant, and embedded metadata.
Example Usage
You are seeding a test database and need 50 unique user IDs. Select UUID v4, set quantity to 50, choose lowercase with hyphens, and click 'Generate'. You instantly get 50 UUIDs like 'f47ac10b-58cc-4372-a567-0e02b2c3d479' ready to paste into your SQL INSERT statements. Alternatively, if you are designing a database schema where sort order matters, choose UUID v7 — the UUIDs will start with a timestamp prefix ensuring that IDs generated later sort after earlier ones, which dramatically improves B-tree index performance compared to random v4 UUIDs.
Benefits
Cryptographically strong randomness ensures virtually zero collision probability for v4 UUIDs. UUID v7 support provides time-ordered identifiers that are optimal for database indexing. Bulk generation saves time when seeding databases or creating test fixtures. The validation and inspection features help debug UUID-related issues. Formatting options (case, hyphens, braces) match any target system's requirements. Everything runs locally — no server calls, no rate limits.