UUID Generator

Free UUID Generator

Generate random UUID v4 identifiers instantly. Bulk generation up to 100 at once. Options for uppercase and no-dash formats. Uses crypto.randomUUID().

Click Generate to create a random UUID v4 identifier using the browser's crypto.randomUUID() method. Each UUID is globally unique with 122 random bits, formatted as five dash-separated hex groups (xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx). Toggle the uppercase option to change output casing, or enable the no-dash option to produce a continuous 32-character hex string without separators. Use the bulk generation feature to create up to 100 UUIDs at once, useful for seeding databases or generating test data. Copy individual UUIDs or copy all at once.

Backend developers generate UUIDs for database primary keys in distributed systems where auto-increment IDs might collide across servers. API engineers create unique request IDs for logging and tracing requests through microservices architectures. Frontend developers generate temporary IDs for optimistic UI updates before receiving server-assigned IDs. QA testers seed test databases with unique identifiers without manually inventing random strings.

UUID v4 provides high uniqueness probability but lacks ordering; if you need sortable IDs, consider UUID v7 or ULID in your production system. Store UUIDs as binary in databases rather than strings to save storage space, converting to string format only for display. When using UUIDs in URLs, the no-dash format creates shorter, cleaner links though standard dash format is more widely recognized. Generate UUIDs programmatically in production code rather than pre-generating batches; this tool is best for testing, prototyping, or one-off data seeding.

All processing happens directly in your browser. Your files never leave your device — no server uploads, no cloud storage, no data retention. The tool works offline once loaded, requires no registration, and is completely free with no usage limits.