Generate one UUID v4
Input and settings
Count: 1
Expected result
One lowercase 36-character UUID with pattern xxxxxxxx-xxxx-4xxx-[89ab]xxx-xxxxxxxxxxxx.
UUID Generator (v4)
Generate 1–100 UUID v4 values, then copy individual IDs or save the whole list as TXT.
How to use
- Choose a count from 1 to 100.
- Generate UUID v4 values.
- Review one value per line, then copy or save TXT.
Generate UUID v4
Inputs and results are not saved or sent. Generating again replaces the current list.
Generated UUIDs
Copy all uses one ID per line without a final newline. TXT adds one final newline (LF) to the same list.
Create identifiers for test data
Set the count to 3 to generate three UUID v4 values. Use a row’s Copy button for one ID. Copy all returns only the UUIDs, one per line, without numbers or labels.
UUID v4 uses 36 characters including hyphens. The following example comes from RFC 9562. This fixed example is not used as generated output.
Example: 919108f7-52d1-4320-9bac-f847db4148a8
Lowercase hexadecimal digits use the 8-4-4-4-12 layout. The first 4 in the third group identifies version 4. New values come from the browser’s standard crypto.randomUUID API. They are not time-ordered IDs or repeatable IDs derived from an input.
Uniqueness is not an absolute guarantee. Use a uniqueness constraint in databases too. UUIDs are identifiers; do not treat them as replacements for passwords or authentication tokens.
Try a use case and check the result
Generate one and three UUID v4 values, checking format and count rather than expecting a fixed identifier.
Example buttons replace the inputs and settings above and calculate. Restore previous input steps back one example at a time. After trying multiple examples, repeat restore to return to your original input. This history is lost when the page closes.
Generate three UUIDs together
Input and settings
Count: 3
Expected result
Three UUIDs with the same v4 format; check that this generated batch contains no duplicates.
How to read the result
The 32 non-hyphen characters are hexadecimal. The third group starts with 4 and the fourth with 8, 9, a or b. UUIDs are identifiers rather than fixed sequential numbers. Downloads store one value per line.
Scope and limits
Count is an integer from 1–100. A secure environment such as HTTPS and browser crypto.randomUUID support are required. Other versions and custom namespaces are unsupported. There is no global database lookup or absolute collision guarantee. Examples replace the list. Restore returns the count only and invalidates the output; it does not recover previous UUIDs.
Verification: predicates independent of the generator check v4/version/variant, lowercase format, count and within-batch uniqueness. Browser checks cover real generation, downloaded text and input restoration after two examples.
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Frequently asked questions
Can I generate v1 or v7?
This tool supports v4 only. It requires crypto.randomUUID in a supported browser on HTTPS. No custom random generator or external API is used.
How can I copy exactly one ID?
Use the Copy button on that row. The read-only field also selects the whole UUID when focused. Check that all 36 characters and hyphens remain at the destination.
Are generated UUIDs saved?
There is no autosave or external transmission. Closing the page clears the list. Use Save TXT or copy to your intended destination to keep the values.
Related tools
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Share only the tool name and public URL. Your input and results are not included.
Inputs and storage
Keep any content you need before clearing. This tool does not autosave inputs or results. Reloading or closing the page, clearing inputs or resetting may discard your work.
Favorites and language preferences are stored separately and may be lost when site data is cleared. Tool resets and site-data deletion do not delete files already downloaded to your device.