UUID
UUID Generator
Generate a UUID v4 by default, switch to UUID v7 when you need time-ordered identifiers, and format the result without uploading anything.
Runs locally in your browser. Your input is not uploaded.
How this tool works
UUIDs are 128-bit identifiers commonly used for database records, API resources, files, and distributed systems.
This general generator lets you choose between random UUID v4 values and time-ordered UUID v7 values, then adjust casing and hyphen formatting.
Examples
- Generate a lowercase UUID v4 for a test record.
- Create a UUID v7 for an event stream where approximate creation order matters.
- Switch between v4 and v7, then confirm casing and hyphen changes do not alter the underlying 128 bits.
Common use cases
When to use the general UUID generator
Use this page when you want one place to choose between UUID v4 and UUID v7, then adjust casing or hyphen formatting before copying. It is best for quick development tasks where the UUID version is part of the decision.
UUID v4 is usually enough for random object IDs, mock records, and request correlation. UUID v7 is more useful when the generated IDs should sort roughly by creation time.
Common mistakes
- Choosing UUID v7 for public IDs without considering that it exposes approximate creation time.
- Removing hyphens before checking whether the target API accepts compact UUID strings.
- Using manually typed UUID-like strings instead of generated values for test data.
Invalid or unsafe assumption
Invalid/failure example
Treating a UUID as proof that a record exists or that a caller is authorized.
Mistakes to avoid
- Using a UUID as an access-control secret.
- Assuming every validator accepts every UUID version.
- Changing textual format without checking a downstream parser.
Limits of this workflow
Generation establishes format and practical uniqueness, not ownership or authorization.
UUID v7 exposes an approximate creation timestamp.
Local-processing and privacy boundary
Values are generated with browser cryptography and are not submitted to DevPouch; copied identifiers can still enter clipboard history.
Practical workflow
- Choose v4 for random identifiers or v7 for time ordering.
- Select the textual format required by the receiver.
- Generate and copy the value.
- Validate it in the target API or database type.
Related guides
Official references
FAQ
Which UUID version should I choose?
Use UUID v4 for general random identifiers and UUID v7 when sorted creation time is useful for databases or logs.
Does this generator send UUIDs to a server?
No. Generation and formatting run locally in your browser.
Can a UUID replace an authorization check?
No. UUIDs identify values; they do not grant access or prove that an object exists.