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UUID Generator

Generate random UUID v4 identifiers instantly. Bulk generate up to 100 UUIDs at once.

0 UUIDs generated
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What is a UUID Generator?

A UUID (Universally Unique Identifier) generator creates random 128-bit identifiers that are statistically guaranteed to be unique across all systems without any central coordination. UUID v4, which this tool generates, uses cryptographically secure random numbers to produce identifiers with a collision probability so low (1 in 2^122) that you could generate one billion UUIDs per second for 85 years before having a 50% chance of a single duplicate. This makes them ideal for distributed systems where multiple services need to independently create identifiers.

How to Use This Tool

  1. Click "Generate UUID" to create one or more UUIDs instantly. Adjust the "Bulk" number to generate up to 100 at once.
  2. Copy the results using "Copy All" to get all generated UUIDs separated by newlines.
  3. Generate more as needed — new UUIDs append to the list, or click "Clear" to start fresh.

Common Use Cases for Developers

  • Database primary keys: Use UUIDs instead of auto-incrementing integers for IDs that don't reveal record count or creation order.
  • API idempotency keys: Generate unique request IDs to prevent duplicate processing in payment APIs and webhook handlers.
  • Distributed systems: Create identifiers across multiple microservices without coordinating with a central ID server.
  • File and asset naming: Generate unique filenames for uploaded files to prevent collisions in object storage (S3, GCS).
  • Correlation IDs: Assign UUIDs to requests for end-to-end tracing across service boundaries in observability systems.

Tips & FAQ

  • UUID v4 format: The format is xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where 4 indicates version 4 and y is one of 8, 9, a, or b (indicating the variant). All other characters are random hexadecimal digits.
  • UUIDs vs. ULIDs: If you need sortable IDs (for database indexing performance), consider ULIDs which encode a timestamp prefix. UUIDs v4 are fully random and don't sort chronologically.
  • Database performance: Random UUIDs cause B-tree index fragmentation in some databases. Solutions include UUID v7 (time-ordered), ULID, or storing UUIDs as binary(16) instead of varchar(36) to reduce storage by 60%.