Generate unique identifiers (UUID)
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Fully random UUID - most common
Generate up to 100 at once
UUID (Universally Unique Identifier) is a globally unique 128-bit identifier. Widely used for database primary keys, session IDs, filenames, etc.
xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxxM: version (4 or 7), N: variant (8, 9, a, b)
A UUID (Universally Unique Identifier) Generator is a tool that creates globally unique 128-bit identifiers following the RFC 9562 standard. UUIDs are essential in distributed systems where unique identification is required without a central coordinating authority. They consist of 32 hexadecimal digits displayed in five groups separated by hyphens (e.g., 550e8400-e29b-41d4-a716-446655440000). With an astronomically low probability of collision, UUIDs are the industry standard for generating unique keys across databases, APIs, and microservices.
Select version
Choose the version that suits your needs: UUID v4 (completely random and general-purpose) or v7 (timestamp-based and sortable).
Option settings
Set the number to generate (1 to 100), letter case, whether to remove hyphens, and other options.
Create UUID
When you click the 'Create UUID' button, UUID matching your settings will be immediately created.
Copy results
Click to copy individual UUID, or use the 'Copy All' button to copy all UUID at once to the clipboard.
UUID v4 ensures complete randomness by generating all 122 bits randomly. UUID v7 includes millisecond time stamps in the upper 48 bits, enabling chronological sorting and excellent database indexing performance. We recommend v4 for general use and v7 for DB primary keys.
UUID v4 values are generated from a 122-bit random space, so the theoretical chance of any specific collision is about 1 in 2^122. Even generating one billion UUIDs per second would take about 85 years to reach a 50% chance of a collision, so duplicates are effectively negligible.
No. All UUID are generated directly on the client utilizing the browser's Web Crypto API. No data is sent to an external server, so you can use it safely.
Yes, the hyphen is for readability and does not affect the uniqueness of UUID. However, the standard format for RFC 4122 is an 8-4-4-4-12 pattern including hyphens, so the format including hyphens is recommended for cross-system compatibility.
Yes, UUID is widely used as DB primary key. In particular, UUID v7 is timestamp-based and is inserted sequentially in the B-tree index, resulting in better indexing performance than v4. However, keep in mind that since it is 128 bits, it uses more storage space than an integer key.