Complete UUID Tool

Our tool is the ultimate solution for developers who need unique identifiers. Whether for databases, APIs, microservices, or any distributed system, you'll find everything you need here.

What our tool offers

We created a comprehensive tool that goes beyond the basics. Besides generating UUIDs instantly, you can analyze existing UUIDs, generate in bulk for large projects, and choose between multiple formats. All with an intuitive interface that works perfectly on desktop and mobile.

When to use our tool?

Our tool is ideal for: Developers who need unique IDs quickly; Teams working with microservices; Creating API tokens; Testing distributed systems; Data migration between environments.

Supported Versions

• UUIDv1: Based on timestamp and MAC address - perfect for debugging and temporal tracking.
• UUIDv3: Uses MD5 hash of namespace and name - ideal for deterministic data.
• UUIDv4: Completely random - our recommendation for most cases.
• UUIDv5: Similar to v3, but with SHA-1 - more secure for critical data.
• UUIDv6: Time-ordered version based on v1, but with layout optimized for B-tree indexes in databases.
• UUIDv7: Latest version with 48-bit Unix timestamp, sortable and optimized for performance in relational databases.
• Nil UUID: Special UUID represented by zeros (00000000-0000-0000-0000-000000000000), useful for testing and null values.

About UUIDs and Supported Versions

UUID (Universally Unique Identifier) is a 128-bit identifier used to generate unique IDs without dependency on a central server. Our tool supports all major versions of the RFC 4122 standard, plus the newer v6 and v7 versions, providing total flexibility for different development needs.

UUID v4 (Random)

UUIDv4 is based on random entropy using cryptographically secure generators (CSPRNG). This is the most popular and recommended version for most modern distributed systems. Since it doesn't depend on hardware information or time, it's ideal for systems that need completely anonymous identifiers with no possibility of leaking information about the generating system.

UUID v1 (Time-based)

UUIDv1 is based on a 60-bit timestamp combined with the MAC address of the generating machine. This version allows tracking the exact moment of identifier creation, which is useful for debugging and temporal analysis. However, it can expose information about hardware and chronological order of creation, which may be a privacy concern in some contexts.

UUID v6 e v7 (Time-ordered)

UUIDv6 and UUIDv7 are newer versions of the standard, specifically designed to solve performance problems in relational databases. UUIDv6 reorganizes v1 bits to improve temporal ordering in B-tree indexes. UUIDv7, in turn, uses a 48-bit Unix timestamp and is completely time-sortable, making it the ideal choice for applications that need efficient sorting in databases like PostgreSQL, MySQL, and MongoDB.

UUID v3 e v5 (Deterministic)

UUIDv3 and UUIDv5 are deterministic versions that generate the same UUID when given the same input parameters (namespace and name). UUIDv3 uses MD5 hash, while UUIDv5 uses SHA-1, offering greater cryptographic security. These versions are ideal for scenarios where you need to generate reproducible identifiers from stable data, such as URLs, DNS names, or other canonical identifiers.

When to Use Each Version

Complete UUID version selection guide

Usage Examples in Different Languages

See how to implement UUIDs in major languages and frameworks

Node.js

Node.js has native support for UUID v4 through the built-in crypto module.

import crypto from "crypto";\nconsole.log(crypto.randomUUID()); // generates UUID v4\n\n// For other versions, use the uuid library\nimport { v1 as uuidv1, v4 as uuidv4, v5 as uuidv5 } from 'uuid';\nconst myNamespace = uuidv4();\nconst name = 'example.com';\nconsole.log(uuidv5(myNamespace, name)); // deterministic UUID v5

Python

Python has the uuid module in the standard library with complete support for all versions.

import uuid\n\n# UUID v4 (random)\nprint(uuid.uuid4())\n\n# UUID v1 (time-based)\nprint(uuid.uuid1())\n\n# UUID v5 (deterministic SHA-1)\nnamespace = uuid.NAMESPACE_DNS\nname = "example.com"\nprint(uuid.uuid5(namespace, name))

PHP

PHP uses the ramsey/uuid library for complete UUID generation.

use Ramsey\Uuid\Uuid;\n\n// UUID v4\n$uuid = Uuid::uuid4();\necho $uuid->toString();\n\n// UUID v1\n$uuid = Uuid::uuid1();\n\n// UUID v5\n$uuid = Uuid::uuid5(Uuid::NAMESPACE_DNS, 'example.com');

Java

Java has native UUID support since version 1.5, with static methods for generation.

import java.util.UUID;\n\n// UUID v4 (random)\nUUID uuid = UUID.randomUUID();\nSystem.out.println(uuid.toString());\n\n// UUID v3 (deterministic)\nUUID namespace = UUID.fromString("6ba7b810-9dad-11d1-80b4-00c04fd430c8");\nString name = "example.com";\nUUID uuid3 = UUID.nameUUIDFromBytes(name.getBytes());

C#

C# has native support through the Guid class in the System namespace.

using System;\n\n// UUID v4 (random)\nGuid guid = Guid.NewGuid();\nConsole.WriteLine(guid.ToString());\n\n// UUID v5 (requires external library like UuidCreator)\n// var uuid5 = UuidCreator.GetVersion5(NAMESPACE_DNS, "example.com");

Ruby

Ruby uses the securerandom gem for UUIDs v4, and the uuid gem for other versions.

require 'securerandom'\n\n# UUID v4\nuuid = SecureRandom.uuid\nputs uuid\n\n# For other versions, use the 'uuid' gem\n# require 'uuid'\n# uuid = UUID.new.generate

Go

Go uses packages like google/uuid for complete UUID generation.

package main\n\nimport (\n    "fmt"\n    "github.com/google/uuid"\n)\n\nfunc main() {\n    // UUID v4\n    id := uuid.New()\n    fmt.Println(id.String())\n    \n    // UUID v5\n    namespace := uuid.NameSpaceDNS\n    id5 := uuid.NewSHA1(namespace, []byte("example.com"))\n    fmt.Println(id5.String())\n}

Using UUIDs in Databases

Native implementations and best practices

MySQL

MySQL offers the UUID() function for generating UUIDs v1 directly in SQL.

-- Generate UUID in INSERT\nINSERT INTO users (id, name, email)\nVALUES (UUID(), 'John Doe', 'john@example.com');\n\n-- Use UUID in a column\nCREATE TABLE users (\n    id CHAR(36) PRIMARY KEY DEFAULT (UUID()),\n    name VARCHAR(100),\n    email VARCHAR(255)\n);

PostgreSQL

PostgreSQL has native support through the uuid-ossp extension, which offers multiple versions.

-- Enable extension\nCREATE EXTENSION IF NOT EXISTS "uuid-ossp";\n\n-- Generate UUID v4\nSELECT gen_random_uuid();\n\n-- Generate UUID v1\nSELECT uuid_generate_v1();\n\n-- Use in table\nCREATE TABLE users (\n    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),\n    name VARCHAR(100),\n    email VARCHAR(255)\n);

SQL Server

SQL Server offers NEWID() for generating GUIDs (equivalent to UUID v4).

-- Generate GUID in INSERT\nINSERT INTO users (id, name, email)\nVALUES (NEWID(), 'John Doe', 'john@example.com');\n\n-- Create column with GUID\nCREATE TABLE users (\n    id UNIQUEIDENTIFIER PRIMARY KEY DEFAULT NEWID(),\n    name NVARCHAR(100),\n    email NVARCHAR(255)\n);

MongoDB

MongoDB uses ObjectId by default, but you can use UUIDs for compatibility with other systems.

// Using UUID in MongoDB with Node.js driver\nconst { v4: uuidv4 } = require('uuid');\n\nconst user = {\n  _id: uuidv4(),\n  name: 'John Doe',\n  email: 'john@example.com'\n};\n\nawait db.collection('users').insertOne(user);

Security and Privacy

All UUIDs are generated client-side in your browser, without sending data to servers. This prevents exposure in external logs and ensures sensitive data never leaves your device.

Client-side generation means all cryptographic processing happens locally in your browser using secure APIs like crypto.randomUUID() or crypto.getRandomValues(). No data is transmitted over the network, ensuring maximum privacy and security.

Entropy quality is crucial for UUID security. Our tool uses cryptographically secure generators (CSPRNG) when available, ensuring generated UUIDs are truly random and unpredictable.

Main Features

• Instant generation in browser - no waiting, no server requests
• Multiple version support - v1, v3, v4, v5, v6, v7 and Nil UUID
• Conversion and analysis of existing UUIDs - understand structure and origin
• Bulk generation - up to 1000 UUIDs at once for testing and import
• Multiple output formats - standard, uppercase, no hyphens
• Responsive interface - works perfectly on desktop, tablet and mobile
• Result download - export UUIDs in text format for later use
• Quick copy - copy all generated UUIDs with a single click

Best Practices and Recommendations

Following best practices when working with UUIDs ensures better performance, security, and code maintainability.

Choose the Right Version

Use UUIDv4 for most distributed systems - it's the safest and most widely accepted. Prefer UUIDv7 if you need efficient time-based sorting in SQL databases. Use v5 when you want to reproduce the same ID from the same data.

Database Storage

In relational databases, use UUID type columns when available (PostgreSQL) or CHAR(36) / BINARY(16) for better performance. Index UUID columns if they're used in frequent queries. Consider sortable UUIDs (v6/v7) for better index performance.

Performance and Indexing

Random UUIDs can fragment B-tree indexes. If insert performance is critical, consider UUIDv7 which is sortable. For range queries, sortable UUIDs are significantly more efficient.

Security

Always use cryptographically secure generators (CSPRNG). Never use UUIDs for authentication or passwords - they are identifiers, not secrets. Avoid UUIDv1 in contexts where privacy is critical, as it may expose hardware information.

Validation

Always validate UUIDs received from external sources using regular expressions or specialized libraries. The standard format is 8-4-4-4-12 hexadecimal characters separated by hyphens.

Readability and Logs

In logs and error messages, UUIDs can be lengthy. Consider truncating to the first 8 characters in informative messages, but always preserve the complete UUID in audit logs.

Why Choose Our Tool?

Comparison with other available UUID generators

There are several online tools for UUID generation, but our solution offers significant advantages that make it the best choice for professional developers.

Detailed Use Cases

REST APIs and Microservices

In microservices architectures, each service needs to generate unique IDs independently without central coordination. UUIDs are perfect for this scenario, allowing different services to create identifiers that will never collide, even in globally distributed systems.

Primary Keys in Databases

UUIDs are excellent alternatives to incremental IDs when you need keys that work across multiple databases or when you need to merge data from different systems without conflicts. UUIDv7 is especially useful for relational databases that need efficient sorting.

Distributed Caching Systems

UUIDv5 allows generating deterministic identifiers for content, enabling distributed caching where the same content always generates the same key, regardless of server.

Temporary File Names

UUIDs are ideal for temporary file names and uploads, ensuring no collisions even in high-concurrency systems.

Session and Event Tracking

UUIDs can be used to track user sessions, analytics events, and transactions in distributed systems, enabling data correlation without dependency on centralized coordinators.

Testing and Development

During development and testing, generating UUIDs in bulk allows quickly creating realistic datasets, simulating load scenarios, and testing distributed system behaviors.

Technical Information

Format and Structure

A UUID is represented as a string of 32 hexadecimal digits organized in five groups separated by hyphens: 8-4-4-4-12 characters. Example: 550e8400-e29b-41d4-a716-446655440000. The total size is 128 bits (16 bytes).

Version Identification

The UUID version is encoded in the 4 most significant bits of the time field (positions 12-15 in hexadecimal format). Possible values are 1-7, with each number representing a specific version of the RFC 4122 standard.

Variant

The variant field occupies the 2-3 most significant bits of the clock_seq_hi_and_reserved field. The RFC 4122 variant is identified by bits 10 (in binary), ensuring compatibility and unique identification.

Collision Probability

For UUIDv4 (random), the probability of generating two identical UUIDs is extremely low. Approximately 2.71 quintillion UUIDs would be needed for a 50% chance of a single collision, making collisions practically impossible in practice.

Main use cases

Our tool is especially useful for:

• Developers who need unique IDs quickly
• Teams working with microservices and APIs
• Testing and developing distributed systems

Tips to get the most out of it

• Use UUIDv4 for most cases - it's the safest and most widely accepted
• UUIDv1 is great when you need to track when something was created
• Generate multiple UUIDs at once to test complex systems
• Analyze existing UUIDs to understand their structure and origin

Everything happens in your browser - no data goes to our servers. Your UUIDs stay only on your device.

If you work with development and need a reliable tool for UUIDs, try our solution. It's free, fast, and complete.