UUID Generator
The UUID Generator produces random version 4 universally unique identifiers in the standard 8-4-4-4-12 hyphenated format, ready to paste into code, databases, and configuration files. How it works: each identifier is generated from random bits with the version and variant fields set per the RFC 4122 specification, giving a value whose collision probability is low enough that the industry treats UUIDs as unique without coordination between systems. Developers use them for database primary keys in distributed systems where sequential IDs leak information and require central authority, for idempotency keys in API requests, for session tokens, file names, test fixtures, and correlation IDs in logs. Because generation runs in your browser, you can produce identifiers without standing up a development environment or remembering the incantation for your language's UUID library — handy on a locked-down machine or when you just need one value for a config file. Tip: when using UUIDs as database keys, store them in a native UUID or binary column type rather than as text where the database supports it; the indexing and storage differences are significant at scale. You can also browse the other tools on the Spark Site home page or search the collection on the tool search page.