Free UUID / GUID Generator Online
Generate random UUID v4 identifiers in bulk.
UUIDs (Universally Unique Identifiers), also called GUIDs, are widely used in software development to uniquely identify records, sessions, and objects. The ToolVerse AI UUID Generator creates RFC 4122 version 4 UUIDs using your browser's secure random number generator, and lets you generate multiple at once.
It generates universally unique identifiers (UUIDs) in the standard v4 format — 36-character strings virtually guaranteed to be unique across systems, commonly used as database keys, session tokens, and object identifiers in software development.
Who should use this tool: Software developers needing unique keys for database records, QA engineers generating test identifiers, API developers creating sample tokens, and anyone building a system that needs collision-resistant unique IDs.
Seeing It in Action
Sample UUID v4 values generated by this tool:
550e8400-e29b-41d4-a716-4466554400006ba7b810-9dad-11d1-80b4-00c04fd430c8f47ac10b-58cc-4372-a567-0e02b2c3d479
UUIDs are used as primary keys in databases, session tokens, tracking IDs, and file names to guarantee uniqueness without a central counter.
Example Output
Generating 5 UUIDs might return values like 3fa85f64-5717-4562-b3fc-2c963f66afa6 — each one 36 characters long, following the standard 8-4-4-4-12 hex pattern with version and variant bits fixed by the v4 spec.
Don't rely on the appearance of a UUID to signal anything about creation order or database sharding. Version 4 UUIDs come from random bits, so two IDs created a millisecond apart can look nothing alike.
Getting Started with UUID / GUID Generator
- Enter how many UUIDs you need (up to 100 at a time).
- Click Generate UUIDs.
- Copy the list of generated UUIDs to your clipboard.
- Paste them into your database, code or configuration file.
What You Get with UUID / GUID Generator
- Generates standards-compliant UUID version 4 values.
- Create up to 100 UUIDs at once.
- Uses the Web Crypto API for secure randomness.
- One-click copy of the entire list.
Why Bother with UUID / GUID Generator
- Quickly create primary keys or test data for databases.
- Generate unique session, request or tracking identifiers.
- No installation of developer tools or libraries required.
Real-World Use Cases
UUID / GUID Generator takes care of the algorithm so you don't have to think about it: Database primary keys.
- Database primary keys: Generate UUIDs to use as unique, non-sequential primary keys for database records instead of auto-incrementing integers.
- API testing: Create sample UUIDs to populate test requests when testing an API endpoint that expects a unique identifier field.
- Session and token identifiers: Generate a unique session token identifier for testing authentication flows during development.
- File and object naming: Use a UUID as part of a filename to guarantee no collision with existing files in a shared storage system.
Worth knowing
Pitfalls to Avoid
The single most common way people get UUID / GUID Generator wrong: Assuming UUIDs are sequential or sortable by creation time.
- Assuming UUIDs are sequential or sortable by creation time. Standard UUIDs are designed to be unique, not chronologically ordered. If you need a naturally sortable identifier, use a sequential numbering scheme instead.
- Treating a UUID as a secret or security token. UUIDs are unique identifiers, not secrets — they're often visible in URLs or logs. Don't rely on UUID unpredictability alone for access control.
- Generating too few UUIDs to check for collisions in critical systems. While UUID collisions are astronomically unlikely, extremely high-volume systems should still follow their platform's recommended UUID version and generation method.
Tips and Best Practices for UUID / GUID Generator
- Understand UUID versions: This tool generates version 4 (random) UUIDs, the most common type for general-purpose unique identifiers — other versions incorporate timestamps or namespace hashing for specific use cases.
- Don't treat UUIDs as secrets: UUIDs are unique, not secret — don't rely on UUID unpredictability alone for security-sensitive access tokens.
- Generate in bulk for seed data: If populating a test database, generate multiple UUIDs at once rather than one at a time.
Common Questions
What is a UUID v4?
A UUID version 4 is a 128-bit identifier that is generated using random or pseudo-random numbers, formatted as 32 hexadecimal digits in the pattern 8-4-4-4-12.
How unique are these IDs really?
The probability of two randomly generated UUID v4 values colliding is astronomically small, which is why they're widely used as unique identifiers in databases and distributed systems.
Can I generate more than 100 at once?
The interface limits a single batch to 100 for readability, but you can click generate multiple times to create as many as you need.
What UUID version does this tool generate?
It generates version 4 UUIDs, which are based on random or pseudo-random numbers, the most widely used format for general application use.
Can I use a UUID as a primary key in a database?
Yes, but be aware of the trade-off: UUID v4 values are random, so inserting them into a clustered/primary-key index causes page fragmentation and slower writes on very large tables compared to sequential IDs. For high-write-volume systems, many teams use UUID v7 (time-ordered) or a bigint auto-increment key instead, and keep UUID v4 as a secondary public-facing identifier.
What's the difference between UUID v4 and UUID v1?
UUID v1 encodes the current timestamp and the generating machine's MAC address, which makes it sortable by creation time but leaks device information. UUID v4 (what this tool generates) is purely random, which sacrifices sortability for privacy and simplicity — it's the safer default for public-facing IDs.
Are UUIDs the same as GUIDs?
Yes, GUID (Globally Unique Identifier) is Microsoft's term for the same underlying concept as a UUID.
Is a UUID safe to use as a public-facing identifier?
Generally yes, since UUIDs don't reveal sequential information about your data the way auto-incrementing IDs can, though they shouldn't replace authentication or authorization checks.