v4 is 122 random bits from the browser's cryptographic generator. v7 (RFC 9562) starts with the Unix time in milliseconds, so v7 IDs sort by creation time — good for database keys. IDs made in the same millisecond still sort in order (a random-increment counter).
Click any UUID to copy it. Copy all copies the whole list in the chosen layout.
Inspect accepts a UUID with or without hyphens, braces, quotes or a urn:uuid: prefix and shows its version, variant and, for v1, v6 and v7, the time it was made.
Shortcut: Ctrl/⌘+Enter copies all.