Options
Choose how many RFC 4122 version 4 UUIDs to create.
Batch size
Generated UUIDs
Created locally with a cryptographically secure random source.
0 UUIDs
No generation yet
Generating UUIDs…
Creating a secure batch in your browser.
About this UUID generator
Generate RFC 4122 version 4 UUIDs using cryptographically suitable random values in the browser. Pick batch sizes from 1 through 100, refresh the list, copy one or all IDs, or download uuids.txt.
How to use
- Select how many UUIDs you need: 1, 5, 10, 25, 50, or 100.
- Click Generate or Refresh to create a new set.
- Copy a single UUID or copy all at once.
- Download uuids.txt to save the batch as a plain-text file.
UUID version 4
Version 4 UUIDs are random identifiers with fixed version and variant bits so they conform to RFC 4122. They are suitable for opaque primary keys when collision risk across your scale is acceptable; they are not guaranteed sortable or sequential.
Common uses
- Seed test databases with unique IDs.
- Generate correlation IDs for local debugging sessions.
- Produce bulk identifiers for fixtures or mock APIs.
Tips
- Regenerate if you need a fresh batch; previous values remain visible until you refresh.
- Store downloaded uuids.txt in version control only when IDs are non-sensitive fixtures.
- For time-ordered IDs, v4 is the wrong tool—look for ULID or UUID v7 elsewhere.
Privacy
UUIDs are created in your browser with no server round trip. ToolsArk does not log or store generated values.
Limitations
- Only version 4 random UUIDs—no v1 time-based or custom namespace IDs.
- Maximum 100 UUIDs per batch on this page.
- Uniqueness is probabilistic; extremely large systems should still handle rare collisions in storage.
Frequently asked questions
Common questions about the UUID Generator.
How does the UUID Generator work?
Choose a batch size (1 through 100), then Generate or Refresh. ToolsArk creates RFC 4122 version 4 UUIDs with the browser’s cryptographic random number generator. Copy one UUID, copy all, or download uuids.txt.
Are UUIDs generated on a server?
No. IDs are generated locally in your browser. Nothing is sent to ToolsArk to create them.
Which UUID version is this?
Version 4 (random). It is not a time-based (v1) or name-based (v3/v5) UUID. Use it when you need unique identifiers without embedding timestamps or namespaces.
Can two UUIDs collide?
Version 4 collisions are theoretically possible but extremely unlikely for normal volumes. Still treat UUIDs as identifiers, not as proof of secrecy or authentication by themselves.
How many UUIDs can I generate at once?
Batch options are 1, 5, 10, 25, 50, or 100. Generate again whenever you need another batch.
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