UUID Generator & Validator

Create random UUID version 4 identifiers for APIs, databases, and tests—or paste a list to verify each value. Up to 10,000 IDs per batch, chunked so the tab stays responsive. Everything runs locally in your browser.

Mode

Maximum 10,000 per run. Large batches are built in small chunks so the page stays usable.

Output

No UUIDs generated yet.

UUIDs are created and checked entirely in your browser and are never uploaded to any server.

HOW IT WORKS

How to generate or validate UUIDs

Pick generate or validate, run the action, and copy the result. Random IDs use your browser’s crypto APIs when available; validation accepts common formatting extras like braces.

Choose a mode

Generate fresh v4 UUIDs or switch to validate to audit a pasted list.

Set count or paste values

Enter how many UUIDs you need (up to 10,000), or paste one identifier per line to check.

Copy the output

Copy generated IDs or the validation summary for specs, seed data, or logs.

Why use this tool

Why generate UUIDs in the browser?

UUIDs are the default primary keys and correlation IDs in many APIs. A quick, private generator avoids shell snippets or pasting into untrusted sites when you just need a handful—or thousands—of values.

Useful when you need to:

Seed test data

Bulk-generate v4 UUIDs for fixtures, mocks, and staging imports without leaving the tab.

Verify pasted IDs

Confirm whether each line is a well-formed RFC-style UUID before merging configs or logs.

Stay on v4

Generation is limited to version 4 (random) so behavior matches what most stacks expect for new keys.

Keep data local

Nothing is sent to a server—suitable for internal IDs and pre-production data.

Privacy

Private and secure

UUID generation and validation use JavaScript in your browser only. Values are not stored, logged, or transmitted.

Data stays on your device

Random bytes never leave memory except when you copy them yourself.

No uploads

Validation compares strings locally; pasted lists are not sent anywhere.

Modern randomness

When supported, generation uses crypto.randomUUID or getRandomValues for unpredictable bits.

FAQ

Frequently asked questions

Version 4 is a random UUID: 122 random bits plus fixed version and variant bits, written as 8-4-4-4-12 hexadecimal groups. It is the most common choice for new database keys.
Practically never for normal use: the space is so large that accidental duplicates are negligible if the random source is good.
Standard hyphenated hex form, case-insensitive, optional braces or urn:uuid: prefix. Nil UUID (00000000-0000-0000-0000-000000000000) counts as valid.
It checks RFC-style structure (versions 1–5 and correct variant bits). v1 and v5 strings can still be valid UUIDs even though this tool only generates v4.
Creating tens of thousands of IDs in one synchronous loop can freeze the page. This tool yields between chunks so the browser can stay responsive.
No. Generation and validation run entirely in your browser; nothing is sent to TinyDataTool or any third party.