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Create random UUID v4 values in standard, uppercase, compact, or brace-wrapped formats without leaving the browser.
What this tool helps you answer
This helps when you need test IDs for records, fixtures, event payloads, or temporary keys.
Next step
Create random UUID v4 values in standard, uppercase, compact, or brace-wrapped formats without leaving the browser.
Editorial review
This page combines the live tool, input guidance, worked examples, and operating limits so UUID Generator: v4, v1 and Bulk stays useful even before users interact with the calculator.
Reviewed by Klartext Tools against the current UUID Generator: v4, v1 and Bulk workflow on 2026-03-19.
Last updated:
Use with judgment
Page scope
This helps when you need test IDs for records, fixtures, event payloads, or temporary keys.
Review the output with Number of UUIDs set to 1-50, then compare it with the method and limitations on this page before changing other inputs.
Change UUID format to standard while keeping the rest of the UUID Generator: v4, v1 and Bulk scenario stable.
If the result moves sharply after changing UUID format, treat the tool output as sensitive and validate the source input before acting.
Choose how many UUIDs you need, select the output format, generate the list, then copy or download it.
Enter how many UUID v4 values you need, from 1 up to 50. Use a higher count when seeding a database table or generating a batch of test record IDs.
Standard lowercase gives the canonical 8-4-4-4-12 form. Uppercase, compact (no hyphens), and brace-wrapped formats are available for systems that expect a different casing or delimiter convention.
Click Generate. All values are created locally using the browser's crypto API, so the output is cryptographically random and never sent to a server.
Click any individual UUID to copy it, use Copy All for the full list as newline-separated text, or download a .txt file when you need to store the batch for later.
This helps when you need test IDs for records, fixtures, event payloads, or temporary keys.
Sample inputs
Sample outcome: Review the output with Number of UUIDs set to 1-50, then compare it with the method and limitations on this page before changing other inputs.
Change UUID format to standard while keeping the rest of the UUID Generator: v4, v1 and Bulk scenario stable.
Sample inputs
Sample outcome: If the result moves sharply after changing UUID format, treat the tool output as sensitive and validate the source input before acting.
UUIDs appear across modern systems because they can be generated without central coordination. A local generator is useful during testing, demos, and data setup.
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