UUID Generator - Generate UUID/GUID Online Free
Generate unique UUID (Universally Unique Identifier) version 4 instantly. Create single or bulk UUIDs for databases, API keys, session tokens, and unique identifiers. Each UUID is cryptographically random and globally unique.
Why Use UUID Generator?
- Globally Unique: Collision probability is virtually zero
- Bulk Generation: Create up to 1000 UUIDs at once
- Multiple Formats: Standard, uppercase, braces, no hyphens
- Standards Compliant: RFC 4122 UUID version 4
Common Use Cases
💾 Database Records
Use as primary keys in distributed databases.
🔑 API Keys
Generate unique identifiers for API authentication.
🎫 Session Tokens
Create secure session identifiers for web apps.
📁 File Names
Generate unique file names to prevent conflicts.
How to Use This Tool
- Choose Quantity: Select how many UUIDs you need (1-1000).
- Select Format: Choose your preferred UUID format.
- Generate: Click generate to create your UUIDs instantly.
💡 Tip: UUIDs are perfect for distributed systems where coordination is difficult.
UUID/GUID Generator
What is a UUID?
A UUID (Universally Unique Identifier), also known as GUID (Globally Unique Identifier), is a 128-bit number used to uniquely identify information in computer systems. The probability of generating duplicate UUIDs is so low it's effectively zero.
UUID Format
A standard UUID v4 looks like this:
550e8400-e29b-41d4-a716-446655440000
It consists of 32 hexadecimal digits displayed in 5 groups separated by hyphens:
- 8 digits - 4 digits - 4 digits - 4 digits - 12 digits
- Total: 36 characters (32 alphanumeric + 4 hyphens)
UUID Versions
UUID v1
Based on timestamp and MAC address. Predictable and can expose system information.
UUID v4
Random generation. Most commonly used. This tool generates v4 UUIDs.
UUID v3/v5
Generated from namespace and name using MD5 (v3) or SHA-1 (v5) hashing.
UUID v6/v7/v8
Newer versions with improved sorting and timestamp features.
Format Examples
Advantages of UUIDs
- Decentralized: Generate without coordination with a central authority
- Mergeable: Merge databases without ID conflicts
- Predictable Size: Always 128 bits (16 bytes)
- Non-Sequential: Harder to guess or enumerate
- Cross-Platform: Works across all programming languages
Common Programming Languages
JavaScript:
crypto.randomUUID()
Python:
import uuid uuid.uuid4()
Java:
UUID.randomUUID()
C#:
Guid.NewGuid()
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