Free online UUID generator for creating unique identifiers and GUIDs. Support for UUID v1, v4, v5 formats with multiple output styles. Professional tool for developers, databases, APIs, and distributed systems.
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Our UUID Generator is a comprehensive tool designed for developers, system architects, and IT professionals who need reliable, unique identifiers for their applications and systems. Supporting all major UUID versions (v1, v3, v4, v5), this tool generates cryptographically secure, globally unique identifiers suitable for databases, APIs, microservices, and distributed systems.
Whether you're developing enterprise applications, managing cloud infrastructure, or building scalable microservices, our UUID generator provides the reliability and flexibility needed for production systems. All UUIDs are generated client-side for maximum security and privacy, with no data transmitted to external servers.
Generated from timestamp and MAC address. Provides time-ordering and can be used to determine creation time. Ideal for scenarios where temporal ordering is important.
Best for: Time-ordered records, audit trails, chronological data
Generated using MD5 hash of namespace and name. Deterministic - same input always produces the same UUID. Useful for creating reproducible identifiers.
Best for: Deterministic IDs, content-based identifiers, reproducible results
Generated using cryptographically secure random numbers. Most commonly used UUID type. Provides excellent uniqueness without revealing any information about the system or time.
Best for: General purpose, database keys, session IDs, API tokens
Similar to v3 but uses SHA-1 hash instead of MD5. More secure than v3 and recommended for new applications requiring deterministic UUIDs. Better collision resistance.
Best for: Secure deterministic IDs, modern applications, enhanced security
550e8400-e29b-41d4-a716-446655440000Most widely compatible format. Used in databases, APIs, and standard applications.
550E8400-E29B-41D4-A716-446655440000Used in some Windows systems, .NET applications, and legacy databases.
550e8400e29b41d4a716446655440000Compact format for storage optimization and URL-safe identifiers.
{550e8400-e29b-41d4-a716-446655440000}Microsoft GUID format used in Windows registry and COM applications.
urn:uuid:550e8400-e29b-41d4-a716-446655440000RFC-compliant URN format for web services and XML applications.
Generate unique primary keys for PostgreSQL, MySQL, MongoDB, and other databases. Avoid auto-increment conflicts in distributed systems.
Create correlation IDs, request tracking, and service communication identifiers for distributed architecture and microservices.
Generate resource identifiers for AWS, Azure, GCP, and Kubernetes deployments. Perfect for infrastructure as code.
UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are essentially the same thing. GUID is Microsoft's term for UUID, typically formatted with braces. Both serve the same purpose of creating unique identifiers.
For most applications, UUID v4 (random) is recommended as it provides excellent uniqueness without revealing system information. Use v1 if you need time-ordering, v3/v5 if you need deterministic UUIDs from input data, and v5 over v3 for better security.
While UUIDs are designed to be unique, they are not 100% guaranteed. However, the probability of generating duplicate UUIDs is astronomically low (approximately 1 in 5.3 x 10^36 for v4). For practical purposes, they are considered unique.
Yes, UUIDs make excellent primary keys, especially in distributed systems. They eliminate auto-increment conflicts, allow offline generation, and work well with database replication and sharding. Consider indexing performance for large datasets.
Most programming languages have built-in UUID support: Java (java.util.UUID), Python (uuid module), JavaScript (crypto.randomUUID()), C# (System.Guid), PHP (uniqid() or ramsey/uuid), and Node.js (uuid package). Use language-specific libraries for production code.
UUIDs are larger than integer IDs (16 bytes vs 4-8 bytes) and can impact database performance due to random insertion patterns. However, they provide significant benefits in distributed systems. Consider UUID v1 or ordered UUIDs for better database performance.
const uuid = crypto.randomUUID();
import uuid
id = str(uuid.uuid4())import java.util.UUID;
String id = UUID.randomUUID().toString();using System;
string id = Guid.NewGuid().ToString();
$uuid = Uuid::uuid4()->toString();
SELECT gen_random_uuid();Our UUID Generator Online is the most comprehensive and professional tool for creating unique identifiers and GUIDs. Whether you're a developer building distributed systems, a database administrator managing primary keys, a system architect designing microservices, or an API developer creating resource identifiers, our generator provides enterprise-grade UUID creation with multiple format options and version support.
Built for technical professionals and enterprise users, this tool supports multiple UUID versions (v1, v4, v5), customizable output formats (standard, uppercase, no-hyphens, braces, URN), and bulk generation capabilities. All UUID generation happens in your browser for maximum privacy and security, with no identifiers stored or transmitted.
Most commonly used UUID version. Generates cryptographically secure random identifiers with no predictable patterns. Perfect for distributed systems, databases, and applications requiring unique identifiers without coordination.
Example: 550e8400-e29b-41d4-a716-446655440000Time-ordered UUIDs based on timestamp and MAC address. Useful for applications requiring chronological ordering of identifiers. Provides guaranteed uniqueness within the same system.
Example: 6ba7b810-9dad-11d1-80b4-00c04fd430c8Deterministic UUIDs generated from a namespace and name using SHA-1 hashing. Ideal for applications requiring consistent identifiers for the same input data across different systems.
Example: 6ba7b810-9dad-5d1-80b4-00c04fd430c8Support for various output styles: standard format, uppercase, no-hyphens, braces notation, and URN format. Choose the format that best fits your application requirements and coding standards.
Standard: 550e8400-e29b-41d4-a716-446655440000UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are essentially the same thing. UUID is the standard term used in most programming languages and systems, while GUID is the Microsoft terminology. Both follow the same RFC 4122 specification and generate 128-bit unique identifiers.
Use UUID v4 (random) for most applications as it provides the best uniqueness guarantees. Use UUID v1 (time-based) when you need chronological ordering of identifiers. Use UUID v5 (name-based) when you need deterministic generation for the same input data across different systems.
While the probability of collision is extremely low (practically zero for most applications), UUIDs are not mathematically guaranteed to be unique. The 128-bit space provides 2^128 possible combinations, making collisions statistically improbable even with billions of generated UUIDs.
Yes, UUIDs make excellent primary keys, especially for distributed systems. They eliminate the need for coordination between database nodes and provide global uniqueness. However, consider that UUIDs are larger than integer keys and may impact performance in very large tables.
UUIDs are 16 bytes compared to 4-8 bytes for integers, so they use more storage. They can also impact index performance due to their random nature. For high-performance applications, consider using UUID v1 (time-based) or implementing proper indexing strategies.
Valid UUIDs follow the pattern: 8-4-4-4-12 hexadecimal characters separated by hyphens. You can use regular expressions or built-in validation functions in most programming languages. Our tool automatically validates generated UUIDs and provides format checking for input validation.
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