UUID Generator

About the UUID Generator

A UUID (Universally Unique Identifier), also called a GUID, is a 128-bit value used as a unique ID without a central authority handing out numbers. Developers use them constantly — primary keys, record and object IDs, correlation IDs in logs and distributed systems, idempotency keys, file names, and anywhere two systems need to mint IDs independently without colliding. This generates version-4 UUIDs, one or many, ready to copy.

How it works

It uses the browser's native crypto.randomUUID(), which produces a version-4 UUID — 122 of its 128 bits are random (the rest encode the version and variant), drawn from a cryptographically secure source. The result follows the canonical xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx format. You can generate up to 100 at once and copy them one at a time or all together, and format them with no hyphens or in uppercase if a system needs that variant.

Assumptions and behaviour

• Generates version-4 (random) UUIDs — the most common kind, where uniqueness comes from randomness rather than timestamp or MAC address.
• Formatting options (remove hyphens, uppercase) are applied for compatibility; the underlying value is the same.
• Uniqueness is probabilistic: with 122 random bits, the chance of ever generating a duplicate is astronomically small — you'd need to generate billions before a collision became even remotely plausible.
• Up to 100 can be generated in a single batch.

Limitations

• It's version 4 only. It doesn't produce time-ordered UUIDs (v1, v6, v7) or name-based ones (v3/v5). If you specifically need database-friendly, sortable IDs, v4's randomness means they won't be ordered by creation time.
• v4 UUIDs aren't sequential, which can fragment database indexes compared with sequential IDs — a known trade-off, not a defect.
• They're identifiers, not secrets — while unguessable in practice, treat security tokens as a separate concern.
• The count is capped at 100 per batch.

Privacy

UUIDs are generated entirely in your browser with its built-in crypto. Nothing is uploaded, logged, or stored.