Bulk v4 UUIDs without a CLI
Migrations, test databases, and mock APIs need unique strings fast. This page generates up to 50 RFC 4122 v4 UUIDs in the tab. One per line, copy the block, paste into .env or SQL.
Generate runs on click and on first load with default count 5. Clear empties the list and disables copy.
Uses crypto.randomUUID when the browser provides it. Fallback path still sets version and variant bits correctly.
Related encoding and ID tools
JWTs are not UUIDs but show up in the same auth debugging session. Inspect segments with the JWT Decoder.
Encode binary or UTF-8 payloads with the Base64 Encoder Decoder. URL-escape query values with the URL Encoder Decoder.
Schedule cleanup jobs for stale rows with the Cron Expression Generator.
Copy and regenerate
Copy list feedback lasts two seconds (Copied! or Copy failed). Regenerate replaces every line; there is no append mode.
IDs are not stored. Refresh the tab and they are gone. That is appropriate for throwaway test data.
Lowercase hex with hyphens matches most ORMs and Postgres uuid type defaults.
Frequently Asked Questions (FAQ)
Which UUID version is generated?
Version 4 random UUIDs. When crypto.randomUUID exists, that API is used. Otherwise crypto.getRandomValues or Math.random fills 16 bytes with v4 variant bits set.
How many UUIDs can I generate at once?
Count input accepts 1 to 50. Generate refreshes the list. Output is one UUID per line for easy paste into env files or spreadsheets.
Is the list copied with newlines?
Copy list grabs the full textarea, including newline between rows. Empty output disables copy until you generate again.
Should I use these for session tokens?
Fine for test fixtures and database seed IDs. Production auth tokens need your stack's recommended generator and storage. Decode existing tokens with the JWT Decoder, not this page.