UUID Generator

Key concepts

The UUID generator makes random UUIDv4 values. It prefers crypto.randomUUID and otherwise fills with getRandomValues. There is no time-based v1 or name-based v5. Generation is browser-only and does not take a server seed. It is often used for database primary-key tests, file names, and request IDs.

Without hyphens you get 32 hex characters, which is easier to fit in length-limited fields. Turn on uppercase only when a legacy system requires it. Generating the same count again changes the values, so copy the list you need immediately. Collision chance is extremely low but is not the only safety net in a distributed design.

Example

Count 5, hyphens on, lowercase yields five lines of standard v4 strings. Uppercase enlarges the hex letters; turning hyphens off makes each line 32 characters. For a test DB, paste the one-per-line result as-is. Use it to trial database keys or reduce file-name collisions; it is not a sequential number. Dropping hyphens yields 32-character hex that fits some legacy field lengths. Generating the same count again changes the values, so copy the list you need right away. When trying the same input several times, reset and paste again so it does not mix with the previous output. On a shared computer, clear the fields when you finish so the original is not left on the monitor. Closing the browser tab also discards what you just pasted; you do not need to send a delete request to a server. Button names and field titles match the tool at the top of the screen, so you can follow along as you read. If the result is empty, first check that required fields are filled and that an error message is not hidden. This article is usage guidance and does not mean input is kept in external storage. On mobile, the copy button may ask for clipboard permission; allow it and press again.

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