JSON Formatter
Make your JSON clean, readable, and easy to debug.
Developer Tools
UUID Generator
Create secure random v4 identifiers in a click.
UUID Generator
Powered by UtilBrixHow to use this tool
- Choose a quantity between 1 and 100.
- Select upper or lower case and whether to include hyphens.
- Generate the identifiers, then copy the list in the format your application expects.
Formula & method
UUID v4 identifiers use the browser cryptographic random source through crypto.randomUUID(). The version and variant bits are set according to the UUID format. Letter case and hyphen options change presentation only.
A practical example
A standard v4 UUID has 36 characters including hyphens, in groups of 8-4-4-4-12. Generate between one and 100 identifiers per run.
When this tool is useful
Create identifiers for test records, fixtures, or a new object before storing it. Batch output is convenient when several independent records need identifiers in the same development workflow.
Common mistakes and limitations
- These are random version 4 UUIDs, not sortable time-based identifiers.
- Removing hyphens changes presentation, but some receiving systems require the standard hyphenated representation.
Frequently asked questions
Can two generated UUIDs collide?
Random UUIDs have a very large identifier space, so accidental collision is extremely unlikely, but not mathematically impossible. Use database uniqueness constraints where uniqueness must be enforced.
Are UUIDs suitable as passwords or authorization checks?
An identifier should not by itself grant access. Validate authorization separately even when record IDs are difficult to guess.