Free UUID Generator

Generate cryptographically random version-4 UUIDs in bulk. Choose how many you need, toggle uppercase or hyphen-less formats, and copy them all at once — ideal for database keys, API IDs, and test fixtures.

Generated UUIDs


    

    



  
Private by design. This tool runs 100% in your browser — your code is never uploaded to any server.

  

    
How to Use the UUID Generator

    
    
      
  1. Set how many UUIDs you need (1–100).
    2. 
      
  2. Toggle uppercase or remove hyphens to match your format.
    3. 
      
  3. Click Generate UUIDs for fresh random values.
    4. 
      
  4. Copy one or copy all to the clipboard.
    5. 
    

  

  

    
Features

    
UUIDs use the Web Crypto API’s cryptographically secure random generator with version-4 and variant bits set per RFC 4122 — not Math.random. Bulk mode generates up to 100 per click, each on its own line, with format options for uppercase hex and compact hyphen-less output, plus copy-all in one click.

    
Benefits & Use Cases

    
Developers seed database primary keys and distributed-system IDs; API designers generate idempotency keys and request IDs; testers create collision-free fixture data. Cryptographic randomness means the values are safe for real uniqueness requirements, generated entirely offline.

    
Tips

    
Use UUID v4 for random IDs; if you need time-ordered IDs for database index performance, look into UUID v7 instead. Store UUIDs as native UUID columns (Postgres) or BINARY(16) rather than VARCHAR(36) for efficiency.

  

  

    
Frequently Asked Questions

    
What is a UUID?
A Universally Unique Identifier: a 128-bit value written as 32 hex digits in 8-4-4-4-12 groups. Version 4 UUIDs are randomly generated, making collisions practically impossible.

    
What is the difference between UUID v1, v4, and v7?
v1 embeds a timestamp and MAC address; v4 is fully random (the most common); v7 combines a timestamp with randomness for time-ordered IDs. This tool generates v4.

    
Are these UUIDs safe to use as database keys?
Yes. They are cryptographically random with correct version/variant bits. For very large tables, consider time-ordered v7 UUIDs for better index performance.

    
Can two UUIDs be the same?
With 122 random bits, generating a duplicate is so unlikely that you would need billions of UUIDs per second for centuries before expecting one collision.

    
Is generation private?
Completely. UUIDs are created locally in your browser via the Web Crypto API — nothing is sent to or stored on any server.

  

  

    
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