🆔 UUID Generator
Generate universally unique identifiers — offline and secure
✓ Free Forever · ✓ No Signup · ✓ No Upload · ✓ Works Offline
🔒 Your data never leaves your device. All processing happens locally in your browser using Web Crypto API (crypto.randomUUID). No upload, no server, no tracking.
Features
- Instant v4 UUIDs — Generate RFC 4122 compliant version 4 UUIDs with a single click.
- Bulk Generation — Generate up to 1,000 UUIDs at once for batch operations.
- UUID Validator — Paste any UUID to check its validity and detect its version.
- Format Options — Output in standard, uppercase, no-hyphens, or braces format.
How It Works
- Click Generate — Get a new v4 UUID instantly. Click again for another.
- Choose format — Select standard, uppercase, no-hyphens, or braces format.
- Bulk generate or validate — Generate multiple UUIDs at once, or paste an existing UUID to validate it.
Use Cases
- Generate unique IDs for database records
- Create correlation IDs for distributed systems
- Generate test data with unique identifiers
- Validate UUIDs from APIs or logs
Frequently Asked Questions
What is a v4 UUID?
A version 4 UUID is a 128-bit identifier generated from random numbers. The probability of a collision is astronomically low — about 1 in 2^122.
Are these UUIDs truly random?
Yes. Every one comes from your browser's crypto.randomUUID(), which draws on the operating system's cryptographically secure random number generator. Nothing is generated on a server.
Can I validate any UUID version?
Yes — versions 1 through 8 from the current standard (RFC 9562), including the newer time-ordered v6 and v7, plus the special nil (all zeros) and max (all F) UUIDs. It accepts the 36-character form, 32 hex digits without hyphens, {braces}, (parentheses) and urn:uuid:. For v1, v6 and v7 it also reads out the timestamp stored inside the UUID.
Notes from Milo 🐨
I pasted a v7 UUID from a Postgres table into my own validator and it told me "Invalid UUID". It only knew versions 1 to 5, so the time-ordered v6 and v7 that a lot of new code produces (plus v8 and the all-zeros nil UUID) were all called broken, while a UUID with a stray bracket or hyphens in the wrong places sailed through. It now follows the current standard: versions 1 to 8, nil and max, the usual spellings including urn:uuid:, and for v1, v6 and v7 it shows the moment the UUID was created. The count box also stopped fighting you: clearing it and typing 50 used to give you 100. You can now make up to 1,000 at once, and pressing Enter in the box generates them.
From the blog
- 📖 How to Generate a UUID (v4) — and When You Actually Need One — Generate one or many random UUID v4 / GUID values in your browser. Learn when to use a UUID as a key and when you should NOT use one as a security token.
Related Tools
- 🔐 Password Generator — Cryptographically secure passwords — generated locally in your browser
- #️⃣ Hash Generator — Generate cryptographic hashes from text or files
- 🕐 Timestamp Converter — Convert between Unix timestamps and human-readable dates
💬 Bug, idea, or just to say hi? Tell Milo 🐨 · [email protected]