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UUID v4 Generator

Securely generate UUID v4 in your browser. Great for test data and DB primary key checks. Supports bulk generation of 1 to 100.

✅ 100% free, no signup, runs entirely in your browser

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📖 How to Use

  1. 1
    Set the count
    Enter a count from 1 to 100. Specifying multiple is handy when bulk-creating test data or DB primary keys.
  2. 2
    Toggle hyphens and click Generate
    Check "No hyphens" to toggle the format, then click Generate. UUIDs are generated with crypto.randomUUID() or Web Crypto API.
  3. 3
    Use the bulk copy
    Click the bulk copy button to copy all UUIDs to the clipboard, newline-separated. Ready to paste into SQL INSERT statements or JSON files.

❓ FAQ

What is UUID v4?
UUID v4 is a 128-bit random identifier defined in RFC 4122 and formatted as 8-4-4-4-12. Version 4 is randomly generated, making collision probability negligibly small in practice.
Is there a risk of collision?
In theory yes, but with 122 bits of randomness, generating 1 trillion UUIDs gives a collision probability below 0.000000001%. Negligible in practice.
Can UUID be used as a database primary key?
Yes. UUID is effective for avoiding duplicates in distributed or multi-server environments. However, UUID v4 is random, which can cause index fragmentation. For ordered inserts, consider UUID v7.