UUID Generator
Free online random UUID generator to create unique identifiers, supporting UUID version 4 and version 7 in single or bulk formats.
UUID Generator
Generate a random UUID instantly for your projects and applications.
UUID version
This generator creates a Version 4 UUID using cryptographically secure browser randomness.
Your UUID will appear here
Click Generate UUID to create a new Version 4 UUID.
How UUID Generator works
Select your UUID version, choose the quantity you need, and generate UUIDs instantly. Copy individual identifiers or use the generated batch for your database, API, testing, or development workflow.
Examples and use cases
Generate Random UUID v4
Create random UUID v4 identifiers for applications, API resources, database records, test data, and general development workflows.
Generate Time-Ordered UUID v7
Create UUID v7 identifiers containing timestamp information so generated identifiers can be naturally ordered by creation time.
Bulk UUID Generation
Generate multiple UUIDs at once for database seed data, mock datasets, testing scripts, migrations, and development workflows.
Generate Database IDs
Create UUID values for database records and application objects when independently generated identifiers are useful for your data model.
Generate API Test Data
Create realistic UUID values for API requests, mock responses, integration testing, staging environments, and software development.
About UUID Generator
A UUID, or Universally Unique Identifier, is a standardized 128-bit identifier used to identify resources, database records, application objects, and digital entities across distributed systems.
Calvyn's free online UUID Generator allows developers to generate UUIDs directly in the browser for database records, API resources, mock test data, application development, and software engineering workflows.
UUID v4 uses randomly generated values for its identifier, making it a common choice when applications need identifiers that can be generated independently without relying on a central sequence.
UUID v7 combines a Unix timestamp with randomly generated data, providing identifiers that are naturally ordered by creation time. This can make UUID v7 useful for database keys and systems where time-ordered identifiers are desirable.
Generating UUIDs independently can reduce the need for centralized ID allocation when working with distributed applications, services, databases, and datasets.
Calvyn generates UUIDs in a standard lowercase hexadecimal representation with hyphens, making them convenient for common database, API, testing, and programming workflows.
Frequently asked questions
What is a UUID?+
UUID stands for Universally Unique Identifier. It is a standardized 128-bit identifier commonly represented as 32 hexadecimal digits arranged in five groups separated by hyphens, producing a 36-character textual representation.
Is this online UUID generator free?+
Yes. Calvyn's UUID Generator is free to use online and provides UUID v4 and UUID v7 generation directly in your browser.
What is UUID v4?+
UUID v4 is a randomly generated UUID version. Most of its bits are generated randomly, making it useful when applications need independently generated identifiers without a central numbering sequence.
What is UUID v7?+
UUID v7 is a time-ordered UUID version that incorporates a Unix timestamp along with randomly generated data. Its structure makes UUID v7 useful when identifiers need to maintain chronological ordering.
What is the difference between UUID v4 and UUID v7?+
UUID v4 primarily uses randomly generated data, while UUID v7 includes a timestamp component followed by additional data. UUID v7 can therefore provide natural chronological ordering, which can be useful for database indexes and time-oriented data.
What is the difference between a UUID and a GUID?+
UUID stands for Universally Unique Identifier, while GUID stands for Globally Unique Identifier. The terms are commonly used interchangeably for identifiers following compatible UUID-style formats, with GUID being especially common in Microsoft ecosystems.
Can two UUIDs ever be the same?+
A UUID collision is theoretically possible, but correctly generated UUIDs are designed to make accidental collisions extremely unlikely. The practical risk depends on the UUID version and generation method being used.
Can I generate multiple UUIDs at once?+
Yes. Calvyn's UUID Generator supports bulk generation, allowing you to create multiple UUIDs at once for test data, database seeding, scripts, migrations, and other development workflows.
Can UUIDs be used as database IDs?+
Yes. UUIDs are commonly used as database identifiers. UUID v4 can provide randomly generated IDs, while UUID v7 can be useful when time-ordered identifiers are desirable for database workloads.
Can I use generated UUIDs in my application?+
Yes. Generated UUIDs can be used for application objects, database records, API resources, test data, and other identifiers when the UUID version and format meet the requirements of your system.
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