Developer utility

UUID generator

Случайные UUID версии 4 — по одному или пачкой, генерация в браузере

Result (0)

About UUIDs

Where they are used

  • • Record and order keys
  • • Session and file identifiers
  • • Idempotency keys and trace IDs

Details

  • • 122 random bits — practically unique
  • • Generated via the Web Crypto API
  • • A UUID is not a secret or a password

UUID: where it is used

Practical use

Primary keys in distributed systems, order and session identifiers, file and upload names, request idempotency keys, trace IDs for logging and debugging integrations.

Batch generation is handy when you need to prepare a set of identifiers in advance for data import or test records.

Characteristics

A UUID takes more space than an auto-increment integer and orders worse — this is worth considering for high-load indexes (there are ordered variants like UUIDv7).

Do not use a UUID as a secret: it is unique but is not a random password or an access token.

Frequently asked questions

What is a UUID?+

A UUID (also GUID) is a 128-bit identifier of 32 hex characters in the form xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. It is used as a unique key for records, files, sessions and entities without centralized number issuance.

How unique are UUIDs?+

A UUID v4 consists of random bits (122 significant). The probability of two generated values matching is negligibly small, so they can be considered unique without checking the database.

Are the UUIDs generated securely?+

Yes, the tool uses crypto (the Web Crypto API) — a cryptographically strong source of randomness in the browser. Values are not sent to a server.

How is version 4 different from others?+

v4 is completely random and does not reveal the time or device of creation — it is the most common variant. v1 is based on time and MAC address, v5 on a hash of a name; for most tasks v4 is enough.