UUID Generator
Generate UUID v4 (random) with multiple format options.
About UUID v4
Format
UUID v4 is 128-bit random: 8-4-4-4-12 hexadecimal digits. The version nibble is always 4 and the variant bits are 10xx.
Use Cases
Unique identifiers for database records, API keys, session tokens, transaction IDs, and distributed systems.
Collision Risk
The probability of generating the same UUID twice is approximately 1 in 2^122, making collisions practically impossible.
Client-side Generation
Uses the browser's crypto.getRandomValues() for cryptographically secure random number generation.
All generation happens locally in your browser. No data is sent to any server.
Technical Specification
UUID/GUID Generation Engine & Version Selection
Overview
The ToolsForges UUID generator produces standards-compliant Universally Unique Identifiers in multiple versions suitable for database primary keys, API request tracking, session management, and distributed system node identification. Select the UUID version — v1 (timestamp-based), v4 (random), or v5 (namespace-based) — and generate single or batch identifiers with proper formatting.
Feature Specifications
- Multi-Version SupportGenerate UUID v1 (timestamp and MAC-based), v4 (cryptographically random), and v5 (SHA-1 namespace-based) to match the specific requirements of different identification use cases.
- Batch GenerationGenerate multiple UUIDs in a single operation for bulk database seeding, test data creation, or distributed system initialization without repeated manual generation.
- Format OptionsOutput UUIDs in standard hyphenated format, uppercase, lowercase, or braced format to match the conventions expected by your database, API, or framework.
- Cryptographic Randomnessv4 UUIDs use the browser's crypto.getRandomValues() API for cryptographically secure random number generation, providing sufficient entropy for collision-resistant identifiers.
Architecture
The generator uses React useState for version and format selection and implements UUID generation algorithms for each version. v4 uses crypto.getRandomValues(), v1 constructs from timestamp and random bytes, and v5 applies SHA-1 hashing.
Frequently Asked Questions
Which UUID version should I use?
Use v4 for most general-purpose identification needs where random uniqueness is sufficient. Use v1 when timestamp ordering is required. Use v5 when you need deterministic UUIDs from a given namespace and name.
How unique are v4 UUIDs?
v4 UUIDs have 122 bits of randomness, providing approximately 5.3 × 10^36 possible values. The probability of collision is astronomically low for any practical application.
Can I use these as database primary keys?
Yes. UUIDs are commonly used as primary keys in distributed databases where auto-incrementing integers are impractical. The random nature of v4 UUIDs may cause index fragmentation in some engines.
Is the generated UUID data stored?
No. All generated UUIDs are produced in-memory within your browser. No identifiers are transmitted to external servers or stored beyond the active session.