UUID Generator & Inspector

Version 4 has 122 random bits. Version 7 begins with 48 bits of Unix time in milliseconds and has 74 random bits. Both use the RFC UUID variant; v7 exposes its timestamp.

No. Generation uses browser Web Crypto randomness and inspection runs locally. IDs are not uploaded or saved automatically; copy and download are explicit actions.

Secure randomness makes collisions unlikely, and this tool rejects duplicates within each generated batch. Absolute global uniqueness is not guaranteed; applications should enforce their own uniqueness constraints.

The timestamp orders IDs from different milliseconds when clocks behave as expected. IDs in one batch share a timestamp and have random order within that millisecond. This tool uses no monotonic counter and cannot guarantee ordering across clock changes.

UUIDs are record identifiers. Use a dedicated password or token generator for authentication secrets. UUIDv7 also reveals an approximate system-clock timestamp.

Standard hyphenated, compact hexadecimal, braced and UUID URN formats are available with optional uppercase letters. TXT contains one ID per line, JSON is an array of strings and CSV has a uuid header.

It checks hexadecimal shape, reads the variant and version, recognizes Nil and Max special values, and decodes standard v7 timestamps. It does not prove uniqueness, randomness, authenticity or authorization.

The inspector accepts one hyphenated UUID, 32 hexadecimal characters, a UUID enclosed in braces or a urn:uuid value. It accepts uppercase or lowercase letters and trims outer whitespace.

A supported browser must provide secure getRandomValues randomness. There is no insecure fallback. Counts must be whole numbers from 1 to 1,000, and v7 requires a representable nonnegative system-clock timestamp.