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UUID v4 Generator

Generate secure random UUID v4 identifiers for databases, APIs, tests, and distributed systems.

Cryptographically secureGenerate up to 1,000Copy and download

How many UUIDs do you need?

Enter any quantity from 1 to 1,000, or use a quick preset.

Generated UUIDs

1 UUID generated successfully.

16f9d43a1-3465-4edf-88a3-a2c0f3c0374d

Technical Specs

Version
UUID v4
Randomness
Secure random bytes
Batch Size
1–1,000
Format
RFC 9562

Globally unique identifiers

Why use UUID v4?

UUIDs let independent services create identifiers without coordinating with a central sequence. Version 4 uses random data, making it practical for database keys, API resources, fixtures, and distributed applications.

What is UUID Generator?

UUID Generator creates version 4 universally unique identifiers from cryptographically secure random bytes. Developers can produce one identifier or a controlled batch, choose conventional hyphenated or compact output, and avoid coordinating a central numeric sequence during testing and distributed workflows.

How to use UUID Generator

  1. 1.Choose how many UUIDs to create within the supported batch limit.
  2. 2.Select lowercase or uppercase output and decide whether hyphens are required.
  3. 3.Generate the batch and inspect the standard version and variant positions.
  4. 4.Copy one value, copy the batch, or download it for an authorized development task.

Key features

  • ✓Secure random bytes provide the unpredictable portion of each UUID v4.
  • ✓Version and variant bits are set to the standard UUID representation.
  • ✓Batch generation supports up to one thousand independent identifiers.
  • ✓Hyphen and letter-case options adapt output without changing the underlying 128 bits.
  • ✓Duplicate detection protects the generated batch before export.

Common use cases

  • Seed identifiers for local database fixtures.
  • Assign correlation IDs to synthetic API requests.
  • Create unique filenames for an offline processing job.
  • Prepare example resource IDs for technical documentation.

Frequently asked questions

What is a UUID v4?

It is a 128-bit identifier whose variable bits are generated randomly while standard version and variant bits identify its format.

Can two generated UUIDs ever be identical?

A collision is theoretically possible, but extraordinarily unlikely when version 4 UUIDs use a secure random source.

Are UUIDs suitable for passwords or secret tokens?

No. Uniqueness is their purpose; use a dedicated cryptographic token generator with an appropriate length for secrets.

Should database UUIDs include hyphens?

Both forms represent the same value, but conventional hyphenated text is widely recognized. Storage and indexing choices depend on the database.

What is the difference between UUID v4 and UUID v7?

Version 4 is random, while version 7 includes sortable time information. This tool generates version 4 values only.

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