UUID Generator Online — v4, v7 & Nil
Generate random UUID v4, time-ordered UUID v7, or the nil UUID. Control hyphens, uppercase, format variants (braces, URN), and how many IDs you need (1–50) for fixtures and seed data.
How generation works
Choose a version, optional formatting (hyphens, uppercase, braces, URN), and a count from 1 to 50. Click Generate to fill the list — copy one line or everything, or download as .txt.
Options
Examples
v4 with hyphens
Settings
Sample output
v7 uppercase, no hyphens
Settings
Sample output
Related utilities
For time-sortable IDs, the ULID generator; for compact IDs, the Nanoid generator. Convert timestamps with the Unix timestamp tool.
UUID generator FAQ
ID generation questions
When should I use UUID v7?
Use v7 when you want IDs that roughly sort by creation time (indexes and debugging). Prefer v4 when you only need random uniqueness.
Is generation private?
Yes. UUIDs are created in your browser with Web Crypto when available.
Why is count capped at 50?
Bulk fixtures are useful; huge dumps are better handled in scripts. Fifty keeps the UI focused while the slider stays practical.
What is the nil UUID for?
It is a reserved all-zero value used as a sentinel or “empty” UUID in some protocols and tests.
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Timestamps, UUID, ULID, Nanoid, cron, passwords, regex, slugify, number bases, case, text diff, and chmod — all client-side.
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