UUID Generator
Generate unique identifiers instantly
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Click generate to create unique identifiers
How to Use This Tool
- Choose how many UUIDs you need — generate a single UUID or a batch of up to 100 at once.
- Select the UUID version: v4 (random) is suitable for most use cases; v1 (time-based) embeds a timestamp.
- Click "Generate" to instantly produce your UUIDs using your browser's crypto API.
- Copy individual UUIDs or use the "Copy All" button to grab the entire list for bulk use.
Common Use Cases
- Generating primary keys for database tables when an auto-incrementing integer is not suitable.
- Creating unique identifiers for distributed systems where multiple nodes generate IDs independently.
- Assigning unique file names when uploading user-generated content to cloud storage.
- Session tokens and correlation IDs for request tracing in microservices architectures.
- Generating unique IDs for draft documents before they are saved to a database.
Frequently Asked Questions
What is the difference between UUID v1 and v4?
UUID v1 is generated from the current timestamp and the machine's MAC address, making it partially predictable. UUID v4 is completely random (122 random bits), making it unpredictable and better suited for security-sensitive identifiers.
Are UUID collisions a real concern?
In practice, collisions are astronomically unlikely. UUID v4 has about 5.3 × 10^36 possible values. Even generating a billion UUIDs per second for the age of the universe would not guarantee a collision.
Can I use UUIDs as database primary keys?
Yes, but be aware that random UUID v4 values can cause index fragmentation in some databases (notably MySQL with InnoDB). UUID v7 (time-ordered) or ULID are better choices for sequential index performance.
Are the UUIDs generated here stored anywhere?
No. All UUID generation happens entirely in your browser using the Web Crypto API. Nothing is transmitted to any server.