UUID Generator: Bulk Version-4 IDs
Runs 100% in your browser — your text never leaves this page, and nothing is uploaded or stored.
This uuid generator creates version-4 UUIDs in the standard 8-4-4-4-12 format — one at a time or up to 500 at once — from your device's cryptographic random source. Use this uuid generator v4 as a bulk uuid generator for database rows, API resources and sessions — up to 500 at once, from your device's cryptographic random source, with hyphens kept or stripped.
How to use the UUID Generator
- Set How many UUIDs you need — one, or a batch of up to 500.
- Tick UPPERCASE letters if the receiving system wants that form, and leave Include hyphens on for the canonical format.
- Click Generate and read the batch in the result box — the note confirms the count and the version.
- Copy the IDs into your code, database seed or API tests.
About this tool
A UUID is a 128-bit identifier so large that random ones effectively never collide — you can mint millions a second and expect every one to be unique on Earth. They label database rows, API resources, files, transactions and sessions wherever a central counter would be a bottleneck. Every result here is a version 4 UUID, and you can read the version right off it: the third group always begins with 4, and the fourth group begins with 8, 9, a or b — fixed bits that mark the format, sitting inside 122 bits of randomness. That randomness comes from your browser’s cryptographic source — the same standard your own apps should use when they mint IDs. Presentation is your choice. Keep the hyphens for databases, logs and anything humans will read or compare; strip them when a system asks for the compact 32-character form. Uppercase when a legacy system expects it — the identifier’s value is the same in either case, only the dress changes. Nothing is registered or stored: each batch is minted locally, exists only on your screen, and is gone when you close the page. Generate up to 500 at a time for seed data, fixtures and test resources. The format generated here, including the version 4 layout, is defined by the IETF standard RFC 9562, the current UUID specification.Worked example
Here is one batch of five, generated with the default settings (hyphens on, lowercase) — yours will be entirely new: SettingsHow many 5 · UPPERCASE off · Include hyphens onYou get (one possible batch)
69f9e266-8be2-44e5-b653-645cbac08899 876b2ccb-557f-4509-9ec4-c83ce73771d2 beb8cdc4-f6be-472c-b2c1-6a02f8475ee0 b2156cd5-58ce-46d5-8340-eaabdd9e458b 3f82e29b-a952-40d7-a507-da3f095bbc59The note reads “5 UUIDs generated (version 4, random).” Check the anatomy on any line: the third group starts with 4 every time — 44e5, 4509, 472c, 46d5, 40d7 — and each fourth group opens with 8, 9, a or b. Those fixed marks are how any system can recognise a version 4 UUID at a glance.
Features
- True version 4 UUIDs from your browser’s cryptographic random source.
- Batches of up to 500 at once, one per line, ready to paste into seeds and fixtures.
- An uppercase toggle and optional hyphens — canonical 8-4-4-4-12 or the compact 32-character form.
- The version readable in every result: third group starts with 4; fourth with 8, 9, a or b.
- Nothing registered or reserved: IDs are minted locally and stored nowhere.
- Private by design: generation happens on your device; no server ever sees your batches.