UUID Generator
Generate UUIDs in every version (v1 through v8, Nil and Max) with bulk generation, validation, timestamp extraction, randomness analysis, and code snippets — all local to your browser.
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What is a UUID?
A UUID is a Universally Unique Identifier: a 128-bit value written as 32 hexadecimal digits in five hyphen-separated groups. Its purpose is to let independent systems create identifiers that will not collide without ever coordinating with each other — no central sequence, no database round trip, no lock.
Version 4, the common one, is essentially random: 122 bits of randomness, which gives a collision space so large that generating a billion a second for a century leaves the chance of a duplicate negligible. That randomness is also its one operational drawback — random identifiers scatter across a database index, which is why time-ordered variants such as version 7 exist for use as primary keys. For everything else, v4 is the sensible default.
Why we built this tool
Developers need UUIDs constantly: seeding test data, creating correlation identifiers for tracing a request across services, naming uploaded files, keying records in a distributed system, or generating idempotency keys for a payment API.
Generating them on a server has always been slightly absurd, because the browser can do it natively and better. Ours uses the Web Crypto API's cryptographically secure random source in your own tab, which means the values are generated on your device and are never transmitted, logged, or seen by us — unlike a server-side generator, where the identifiers you are about to use exist in someone else's request log. It is also instant and works with no connection at all.
Tips and common mistakes
- Version 4 is the right default; reach for a time-ordered variant only if index fragmentation is a measured problem.
- Never treat a UUID as a secret — it is unique, not unguessable in the security sense that matters for access control.
- Store UUIDs in a native binary or UUID column where your database offers one rather than as 36-character text.
- Keep the hyphens unless a downstream system specifically rejects them; they are part of the canonical form.
Open UUID Generator with a link
UUID Generator can be handed its input by the link that opens it, so the page arrives with the work already done. This is meant for assistants and scripts: if a chatbot, an editor extension, or a command-line agent already holds your content, it can build a link instead of asking you to copy and paste into a box.
The payload rides in the fragment — the part of a URL after the #. Browsers never send the fragment to a server, so anything handed over this way stays on your device exactly as a dropped file would. A link that uses the query string instead is rewritten into the fragment by the page before any analytics or ad script can read the address.
#count=— how many to produce
Example: https://mygadgets.ink/tools/uuid-generator/#count=...
Quick start: using UUID Generator
- Open the tool and generate a UUID with one click.
- Choose how many you need if you are seeding a batch of test data.
- Select the formatting you want, such as uppercase or hyphen-free, if offered.
- Copy the values straight to your clipboard.
- Use version 4 unless your database specifically benefits from time-ordered keys.
For non-identifier randomness, see Random Number Generator, and Lorem Ipsum Generator for placeholder text to go with your test records.