Free UUID / GUID Generator Online
Generate UUID v4 instantly Bulk generate up to 100,000 Export as TXT, CSV, JSON
UUID Format
Separator
⚡ Single UUID v4
v4📦 Bulk UUID Generator
📖 About UUID v4
Cryptographically Random
UUID v4 uses 122 bits of randomness from crypto.randomUUID() —collision probability is astronomically small.
RFC 4122 Compliant
Follows the official UUID specification. The 13th digit is always '4' (version) and the 17th is '8', '9', 'a', or 'b' (variant).
Standard Format
Always 36 chars: 8-4-4-4-12 hex groups separated by hyphens. Example: f47ac10b-58cc-4372-a567-0e02b2c3d479
Use in Databases
Perfect as primary keys in PostgreSQL, MySQL, MongoDB, or any database. Globally unique without a central coordinator.
100% Private
All UUIDs are generated in your browser. Nothing is sent to our servers —generation is instant and offline-capable.
Unlimited & Free
Generate up to 100,000 UUIDs in one click. No sign-up, no watermark, no limits on usage.
About UUID Generator
Looking for a free UUID generator online? This tool generates cryptographically random UUID v4s instantly — one at a time or in bulk up to 100,000. Download your UUIDs as TXT, CSV, or JSON. Supports multiple formats including lowercase, UPPERCASE, {GUID braces}, and URN notation. No login, no server calls, 100% free.
Whether you need a single unique ID for a database record, or thousands of UUIDs for bulk data seeding, testing, or generating unique keys — this tool does it all instantly in your browser.
All UUIDs are generated using your browser's crypto.randomUUID() API, which produces cryptographically strong random identifiers that comply with RFC 4122.
How to Generate UUIDs Online
- Choose your output format (lowercase, UPPERCASE, braces, or URN)
- Click "Generate" for a single UUID, or select a bulk count
- Copy individual UUIDs or click "Copy All" for the full list
- Download as TXT, CSV, or JSON for use in your project
UUID Formats Supported
- lowercase: f47ac10b-58cc-4372-a567-0e02b2c3d479
- UPPERCASE: F47AC10B-58CC-4372-A567-0E02B2C3D479
- GUID braces: {F47AC10B-58CC-4372-A567-0E02B2C3D479}
- URN: urn:uuid:f47ac10b-58cc-4372-a567-0e02b2c3d479
What is UUID v4?
UUID (Universally Unique Identifier) v4 is a 128-bit random identifier formatted as 32 hexadecimal digits separated by hyphens in the pattern 8-4-4-4-12. Version 4 uses 122 bits of randomness, making the probability of collision virtually zero — around 1 in 5.3×10³⁶.
Use Cases
- Primary keys in PostgreSQL, MySQL, MongoDB, DynamoDB
- Unique session tokens and API keys
- Test data seeding and database population
- Distributed system IDs with no central coordinator
- Filename deduplication and asset naming
- Correlation IDs in microservices and logging