What UUID Generator helps you do

Create random UUID v4 identifiers for database keys, correlation IDs, test fixtures, and API resources. Generate one ID or a batch of up to 100, then copy the list into configs, seeds or tests. The values come from the browser's cryptographic random generator, so they are suitable for identifiers that must not collide.

UUIDs are generated in your browser with cryptographic randomness. Haivix does not log generated values.

How it works

The page calls crypto.randomUUID() for each value, which produces a version 4 UUID from the browser's cryptographic random source. The count is clamped between 1 and 100 so the textarea and clipboard stay responsive. Nothing is stored or sent to a server.

How to use UUID Generator

Choose how many UUIDs to generate, up to the tool limit.
Select Generate to create the list.
Copy a single value or the full list for configs, seeds, or tests.
Keep the generated list with the fixture if the tests depend on it.

When to use it

Seed local databases with unique primary keys during development.
Create correlation IDs for log tracing across microservices.
Produce test data sets that need globally unique identifiers.
Generate request IDs for an API client or a queue message.
Create stable keys for local cache entries.
Fill a fixture with IDs that will not collide with production data.
Tag a one-off script run so its log lines can be grouped.
Generate IDs for a batch import that has no natural key.
Create a request ID for a webhook retry.

When not to use it

Do not use a UUID as a secret or a password; it is an identifier, not a credential.
Do not expect time-ordered IDs; v4 values are random and not sortable by creation time.
Do not generate more than the batch limit in one click; run it again for another batch.

Example

A test fixture needs 40 user records. The generator produces 40 v4 UUIDs, which are pasted into the seed file as primary keys. The file is committed with the IDs so the test assertions can reference the same values on every run.

What you can do with UUID Generator

Generate a single UUID v4 or a batch of up to 100.
Use crypto.randomUUID() for cryptographic randomness.
Copy the whole generated list in one action.
Get correctly formatted 8-4-4-4-12 identifiers.
Regenerate as often as needed.
Keep generation local to the browser.
Generate the same batch size again with one click.

Example: seed a test database

Set the count to the number of records the fixture needs and generate the list. Copying all values at once is faster than generating them one at a time.

Paste the list into the seed file or a spreadsheet column and keep the order if it maps to records. The values are independent, so the order does not affect uniqueness.

Store the generated IDs with the fixture. Regenerating produces different values, which would break references in tests that already use them.

What to know before you start

Only UUID v4 is offered; there are no v1, v3, v5 or v7 options.
The batch is capped at 100 values per generation.
The tool does not persist or export a history.
A v4 UUID is random, not time-sortable.
It is not a password or secret generator.

Common mistakes

Regenerating the list after the fixture was written and breaking the references.
Using a UUID where a sortable, time-based key is needed.
Treating the value as unguessable enough to act as an API token.
Copying only part of the list and losing a value in the middle.
Assuming the tool stores the last batch after a reload.
Using a UUID column that is shorter than 36 characters.
Using a UUID as a customer-facing order number.

Troubleshooting

If the count does not change, the field is clamped to the supported range. Enter a value between 1 and 100.

If copy fails, select the textarea manually; clipboard access can be restricted in some browser contexts.

If the list disappears after a reload, that is expected; nothing is stored. Generate a new batch and save it with the fixture.

If a system rejects a UUID, check whether it expects a specific version, uppercase hex, or no hyphens.

If two systems show different values, confirm that the ID was not regenerated between them.

If a database column is too narrow, remember that a canonical UUID is 36 characters with hyphens, or 32 without. Store it as a native UUID type where the database supports one.

UUID Generator