UUID Generator
Generate universally unique identifiers instantly. v1, v3, v4, v5, v7 — with validation, decoding, and bulk export.
v1, v3, v4, v5, and v7 — the full RFC 4122 set plus the modern Unix-epoch v7.
Lowercase, UPPERCASE, no hyphens, braces, URN prefix, and Base64 encoding.
Generate up to 10,000 UUIDs and export as TXT, JSON, CSV, or SQL.
Paste any UUID to validate it and decode the embedded timestamp, version, and variant.
Free Online UUID Generator — Generate Unique Identifiers Instantly
Welcome to uuid-generate.com, the fastest and most reliable free UUID generator online. Whether you're a developer building distributed systems, a database architect designing tables, or a software engineer implementing microservices, our tool provides RFC 4122 compliant UUIDs for all your needs.
What is a UUID?
UUID (Universally Unique Identifier) is a 128-bit identifier standardized by RFC 4122. Originally developed by the Open Software Foundation, UUIDs are designed to be unique across all systems without requiring a central authority. The probability of generating duplicate UUIDs is so low that you could generate UUIDs every second for billions of years and never encounter a collision.
UUID Versions Explained
Our UUID generator supports all major UUID versions. UUID v1 is time-based, using the current timestamp and a randomly generated node ID. UUID v3 and v5 are namespace-based, generating deterministic identifiers using MD5 or SHA-1 hashing. UUID v4 is the most popular version, using cryptographically secure random numbers for maximum entropy. UUID v7 is a newer standard using Unix timestamp with random components, ideal for database indexing.
Why Use Our UUID Generator?
Unlike other tools, we offer a free UUID generator with no ads, no registration, and no usage limits. Our tool generates RFC 4122 compliant identifiers entirely in your browser, ensuring your data never leaves your device. The UUID v4 generator uses cryptographically secure random values from the Web Crypto API, making it suitable for security-sensitive applications.
Key Features
- Multiple UUID versions: Generate v1, v3, v4, v5, and v7 UUIDs online
- Flexible output formats: Get lowercase, uppercase, with or without hyphens, or with braces
- Bulk generation: Create thousands of UUIDs and export as TXT, JSON, CSV, or SQL
- UUID validation: Verify if a string is a valid UUID
- UUID decoding: Extract timestamp and version information from time-based UUIDs
- Developer-friendly: Keyboard shortcuts and instant copy functionality
Common Use Cases
Database Primary Keys: UUIDs serve as excellent distributed primary keys, eliminating the need for sequential IDs and central coordination. Each database node can generate unique identifiers independently. Microservices Architecture: In distributed systems, UUIDs prevent ID collisions when multiple services generate identifiers without communicating. API Keys and Tokens: The high entropy of v4 UUIDs makes them suitable for generating secure API keys and session tokens. Logging and Debugging: Unique identifiers help trace requests across microservices and correlate logs.
How to Use This Tool
Using our UUID generator online is simple. Select your desired UUID version from the tabs above. For v3 and v5, enter a namespace and name to generate deterministic UUIDs. Click the generate button or press Ctrl+G to create a new identifier. Copy it instantly with Ctrl+Shift+C or by clicking the UUID display. Choose your preferred format using the format toggles below the generated UUID.
Browser-Based Generation
All UUID generation happens client-side using JavaScript. Your browser's Web Crypto API provides cryptographically secure random values for v4 UUIDs. This means no data is sent to any server, ensuring privacy and security. The tool works offline once loaded and works in all modern browsers.
Bulk UUID Generation
Need to generate UUID in bulk? Visit our bulk generator page to create thousands of UUIDs at once. Export in multiple formats including plain text, JSON arrays, CSV files, and SQL INSERT statements. Perfect for seeding databases, testing applications, or generating sample data.
UUID Validator and Decoder
Use our UUID validator to check if a string is a valid UUID. The UUID decoder extracts information from time-based UUIDs (v1 and v7), showing the timestamp, version, and variant. These tools are invaluable for debugging and analyzing UUIDs in your applications.
For Portuguese Speakers (Brasil)
Our gerador de UUID também está disponível em português do Brasil. Você pode gerar UUID gratuitamente para suas aplicações. O gerador UUID suporta todas as versões (v1, v3, v4, v5, v7) e oferece exportação em múltiplos formatos. Perfeito para desenvolvedores brasileiros que precisam de identificadores únicos para seus projetos.
Start using our free UUID generator today. No ads, no tracking, just fast and reliable UUID generation.
What is a UUID?
UUID (Universally Unique Identifier) is a 128-bit identifier standardized by RFC 4122. It is designed to be unique across all systems without requiring a central authority. UUIDs are typically represented as 32 hexadecimal characters displayed in five groups separated by hyphens.
What is a UUID generator?
A UUID generator is a tool or software that creates universally unique identifiers automatically. It can generate different versions of UUIDs (v1, v3, v4, v5, v7) based on specific algorithms including time-based, name-based (MD5/SHA-1), random, and Unix epoch-based methods.
How do I generate a UUID?
To generate a UUID, select your desired version (v1, v3, v4, v5, or v7) from the version selector, and click the Generate button or press Ctrl+G. The UUID appears instantly in your chosen format. You can copy it with Ctrl+Shift+C or by clicking the UUID display.
What is UUID v1?
UUID v1 is a time-based UUID generated from the current timestamp (100-nanosecond intervals since Oct 15, 1582) and a node ID (typically MAC address). Version 1 UUIDs are sortable by creation time, making them useful for database primary keys where chronological ordering matters.
What is UUID v4?
UUID v4 is a random UUID generated using cryptographically secure random numbers. It provides a 122-bit random component, ensuring near-zero collision probability (~1 in 5.3×10³⁶). It is the most widely used UUID version for general-purpose unique identifiers.
What is UUID v6?
UUID v6 is a reordered variant of v1 that maintains timestamp-based sorting while hiding the node ID. It provides lexicographically sortable UUIDs with privacy improvements over v1, though it is less commonly supported than v1, v4, or v7.
What is UUID v7?
UUID v7 is a modern UUID format standardized in RFC 9562. It encodes the current Unix timestamp in milliseconds in the most-significant bits, followed by random bits. V7 UUIDs sort lexicographically by creation time and work great as database primary keys.
What is the difference between UUID v4 and UUID v7?
UUID v4 uses completely random numbers for all bits (except version/variant), while UUID v7 embeds a Unix timestamp in the first 48 bits followed by random bits. V4 provides maximum entropy but unsorted output, while v7 provides time-based sorting with minimal collision risk. V7 is better for database indexes where chronological order matters.
Are UUIDs unique?
UUIDs are designed to be universally unique. UUID v4 has a collision probability of approximately 1 in 5.3×10³⁶ — so low that generating UUIDs every second for billions of years would likely never produce a duplicate. UUID v1 and v7 are also unique within their generation scope.
Are UUIDs random?
It depends on the version. UUID v4 is completely random (122 random bits). UUID v1 uses a timestamp and node ID. UUID v3/v5 use MD5/SHA-1 hashes of a namespace and name (deterministic). UUID v7 uses a Unix timestamp plus random bits. So some versions are random, while others are time-based or deterministic.
Can I generate multiple UUIDs at once?
Yes, visit our Bulk Export page to generate up to 10,000 UUIDs at once. You can export them as TXT, JSON, CSV, or SQL files. This is perfect for seeding databases, testing applications, or generating sample data.
Is there a free UUID generator?
Yes, uuid-generate.com is completely free to use. No registration required, no ads, and no usage limits. All UUID generation happens client-side in your browser, ensuring privacy and security.
Can I use UUIDs in a database?
Yes, UUIDs are commonly used as primary keys and unique identifiers in databases. UUID v4 provides randomness, while v1 and v7 offer time-based sorting. Note that random UUIDs (v4) can cause index fragmentation in some databases, so consider v7 for better insert performance.
What is the difference between UUID and GUID?
UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are essentially the same thing. GUID is Microsoft's implementation of the UUID standard. Both are 128-bit values with the same format and behavior. The terms are often used interchangeably.
Can I generate UUIDs offline?
Yes, once the uuid-generate.com page is loaded, you can generate UUIDs offline. All generation happens client-side in your browser using the Web Crypto API. Your browser's cryptographically secure random number generator creates the UUIDs locally.
Are generated UUIDs stored?
No, uuid-generate.com does not store any generated UUIDs. All generation occurs client-side in your browser. The UUIDs you generate are never sent to any server, ensuring complete privacy and security. Once the page is closed, no trace of your generated UUIDs remains.
How do I copy a UUID?
Click anywhere on the UUID display to copy it instantly. You can also use the keyboard shortcut Ctrl+Shift+C (or Cmd+Shift+C on Mac) to copy the formatted UUID. The nav bar also has a quick copy button when available.
What format does a UUID use?
A standard UUID uses the format 8-4-4-4-12 hexadecimal characters with hyphens, like: 550e8400-e29b-41d4-a716-446655440000. This represents 32 hexadecimal digits (0-9, a-f) displayed in five groups separated by hyphens. Total length is 36 characters including hyphens.
Can I use generated UUIDs commercially?
Yes, you can use generated UUIDs commercially without restriction. UUIDs are mathematical constructs and cannot be copyrighted or owned. They are free to use in any application, database, or commercial product. The uuid-generate.com tool simply generates them for you.
How many UUIDs can I generate?
There is no limit to how many UUIDs you can generate on uuid-generate.com. You can generate one at a time on the main page or up to 10,000 UUIDs at once using our Bulk Export feature. All generations are completely free with no usage caps.
Generate thousands of UUIDs and download as TXT, JSON, CSV, or SQL.