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Vanity UUID Generator

Used by developers, writers, and creators worldwide.

A vanity UUID generator lets you embed a recognizable hex prefix into the first segment of any UUID, making identifiers instantly spottable in logs, seed files, and debug output. Instead of scanning walls of random characters, you see records like deadbeef-... or cafebabe-... at a glance. The rest stays randomly generated and version 4 compliant, so uniqueness guarantees hold. This is especially useful during development when you need to seed databases with test records that are easy to grep or filter. A prefix like testfeed or deadc0de isolates demo data from real data without adding extra columns to your schema. Enter any hex string up to 8 characters, set a batch count, and copy the results straight into your project.

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How to use

  1. Choose your options above
  2. Click Generate
  3. Copy your result

Detailed instructions

  1. Type your desired hex prefix (up to 8 characters from 0-9, a-f) into the Prefix field.
  2. Set the Count field to how many vanity UUIDs you need in this batch.
  3. Click Generate to produce the list of UUIDs with your prefix in the first segment.
  4. Copy individual UUIDs or the full list, then paste directly into your code, fixture file, or database seed script.

Use Cases

  • •Seeding a Postgres staging database with deadbeef-prefixed rows you can purge with a single WHERE LIKE query
  • •Generating fixture files for Jest or Vitest where human-readable primary keys make failed assertions easier to read
  • •Producing demo API responses in Postman collections where branded UUIDs signal example data to reviewers
  • •Tagging synthetic load-test records in k6 or Locust scripts so they can be identified and deleted after a run
  • •Creating consistent example UUIDs for technical blog posts or conference live-coding demos

Tips

  • →Use a prefix that encodes the entity type, like c0de0001 for code entities, so logs self-document.
  • →Keep prefixes to 4-6 characters rather than 8 to retain more randomness in the first segment.
  • →Pair vanity UUIDs with a SQL LIKE 'yourprefix%' index for fast test-data cleanup queries.
  • →Avoid prefixes starting with 0000 in systems that sort UUIDs lexicographically — they cluster at the top of indexes.
  • →Use the same prefix across an entire test suite run to make teardown deterministic and auditable.
  • →For API docs, generate one canonical set of vanity UUIDs and reuse them across all examples so readers see consistent IDs.

FAQ

are vanity UUIDs valid in PostgreSQL or MySQL

Yes. Both databases accept any correctly formatted UUID regardless of what the first segment contains. In PostgreSQL you can store them as the native uuid type; in MySQL use CHAR(36) or BINARY(16). The vanity prefix has no effect on indexing performance — it behaves identically to a fully random UUID.

what hex words can I use as a UUID prefix

Several English words are valid hexadecimal: cafe, face, fade, bead, beef, dead, decade, facade, and combinations like deadbeef or cafebabe. Using a real word makes your prefix memorable and easy to communicate verbally when discussing specific record groups with teammates.

does a custom prefix reduce UUID uniqueness enough to cause collisions

Not meaningfully. An 8-character prefix fixes only the first segment; the remaining three segments are still randomly generated, leaving around 96 bits of entropy per UUID. For seeding test data, documentation, or demo datasets, the collision probability is negligible.