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Identifier Utility

UUID Generator

Generate random v4 UUIDs in your browser for tests, database seeds, API examples, fixtures, and temporary identifiers. Copy one UUID or create a whole list.

UUID examples and workflows

Use this UUID generator for fixtures, database seeds, API tests, mock records, and temporary identifiers.

How to use this tool

  1. Choose how many UUIDs to generate.
  2. Toggle uppercase or remove hyphens if your system needs that format.
  3. Copy the list, download it, or validate an existing UUID.

Real examples

  • Generate 12 UUIDs for local database seed records.
  • Create uppercase identifiers for legacy imports.
  • Validate 550e8400-e29b-41d4-a716-446655440000 from an API response.

Common use cases

  • Mock API payload IDs during frontend development.
  • Create stable-looking fixture data for tests.
  • Check whether a pasted value matches UUID format.

Sample input/output

  • Generate: set quantity to 3 and click Generate UUIDs.
  • Output: one v4 UUID per line, ready for JSON, CSV, or SQL fixtures.
  • Validate: paste a known UUID to confirm version and formatting.

Common errors and fixes

  • Validation fails: check missing groups, extra spaces, or non-hex characters.
  • Import needs no hyphens: turn off Include hyphens before copying.
  • Legacy system wants uppercase: enable Uppercase without changing UUID semantics.

Edge cases table

Case What to know
v4 UUID Random identifier, useful for fixtures and client-side temporary IDs.
No ordering v4 UUIDs do not encode creation time and should not be used for time sorting.
Format check Validation confirms shape, not whether the ID exists in your database.

Edge cases / errors

  • Generated values are random v4 UUIDs, not time-based UUIDs.
  • Removing hyphens changes formatting, not the underlying random value.
  • The validator checks format, not database uniqueness.

Move between browser-local utilities for developer data and debugging.

URL Encoder / Decoder

Encode and decode URL components locally.

Base64 Encoder / Decoder

Encode and decode UTF-8 text.

Timestamp Converter

Convert Unix timestamps and dates.

CSV to JSON Converter

Turn CSV rows into JSON locally.

UUID Generator FAQ

Practical details about UUID generation and validation.

Does this use a server?

No. UUIDs are generated locally with browser cryptography APIs.

Which UUID version is generated?

This tool generates random version 4 UUIDs.

Can I generate many UUIDs?

Yes. Generate up to 100 at a time and copy or download the list.

Can I validate UUIDs?

Yes. Paste a value into the validator to check standard UUID format.