What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify resources in distributed systems. UUIDs are widely used as database primary keys, API identifiers, session tokens, and tracking IDs.

Privacy First: All UUIDs are generated entirely in your browser using the Web Crypto API. No server requests, no data collection, nothing stored or transmitted.

UUID Versions Explained

This tool generates three commonly used UUID versions, each optimized for different use cases:

UUID v1 Timestamp

Based on current timestamp and random node. Useful when you need time-ordered identifiers with extractable creation time.

UUID v4 Random

Fully random using 122 bits of cryptographic data. The most commonly used version, ideal for general-purpose unique identifiers.

UUID v7 Sortable

Combines Unix timestamp with random data (RFC 9562). Sortable by creation time, making it excellent for database primary keys.

Table of Contents

1. What is a UUID?
- 1.1. UUID Versions Explained
2. How to Use
3. Features
4. Frequently Asked Questions

How to Use

Generate a Single UUID

Select Version

Click a version tab (v1, v4, or v7) to choose your UUID type. A UUID is automatically generated when you open the tool.

Generate or Copy

Click Generate to create a new UUID, or Copy to copy the current UUID to your clipboard instantly.

Format Options

Customize the UUID output with checkboxes below the display. All format options apply in real time:

Uppercase — Convert to uppercase letters (e.g., 550E8400-E29B-...)
No hyphens — Remove dashes for compact format (e.g., 550e8400e29b...)
Braces {} — Wrap in curly braces (e.g., {550e8400-...})
Quotes "" — Wrap in double quotes (e.g., "550e8400-...")

Bulk Generation

Configure Quantity

Set the quantity (1 to 1,000) and choose a separator (newline, comma, or semicolon) for your output format.

Generate & Export

Click Generate to create multiple UUIDs at once. Use Copy All or Download to export as TXT, JSON, or CSV files.

UUID Decoder

Inspect any UUID's internal structure and properties:

Input UUID

Expand the UUID Decoder section at the bottom. Paste any UUID and click Decode (or press Enter).

View Details

Instantly view the UUID's version, variant, timestamp (for v1 and v7), and raw hex value. Accepts UUIDs with or without hyphens, braces, and quotes.

Features

Three UUID Versions

Generate UUIDs in the three most commonly used versions, each suited for different use cases:

v1 (Timestamp) — Encodes creation time and random node identifier for audit trails
v4 (Random) — 122 bits of cryptographically secure random data for general use
v7 (Sortable) — Unix timestamp with random bits (RFC 9562) for database optimization

Flexible Formatting

Customize output format with one-click options that apply to both single and bulk UUIDs in real time:

Uppercase letters for consistency
Remove hyphens for compact format
Add curly braces or double quotes
All formats work instantly

Bulk Generation

Generate up to 1,000 UUIDs at once with flexible export options:

Choose separator: newline, comma, or semicolon
Export as TXT, JSON, or CSV files
Copy all to clipboard instantly
Perfect for database seeding

UUID Decoder

Paste any UUID to instantly inspect its internal properties:

Version number and variant type
Creation timestamp (v1 and v7)
Raw hex value breakdown
Accepts any UUID format

Frequently Asked Questions

Which UUID version should I use?

For most cases, UUID v4 is the standard choice — it's random, simple, and widely supported across all platforms and programming languages.

If you need time-sortable IDs for databases, use UUID v7 — it preserves insertion order and improves index performance by reducing B-tree page splits.

Use UUID v1 when you need to extract the creation timestamp from the ID itself, useful for audit trails and time-based analysis.

Can UUIDs collide?

UUID v4 uses 122 random bits, giving approximately 5.3 × 10³⁶ possible values. The probability of a collision is astronomically low.

To put this in perspective: you would need to generate about 2.7 × 10¹⁸ (2.7 quintillion) UUIDs to have a 50% chance of encountering just one duplicate.

Practical Reality: In real-world applications, UUID collisions are so rare that they're considered statistically impossible. You're more likely to win the lottery multiple times.

What is the difference between UUID and GUID?

UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) refer to the same thing. The format and structure are identical.

UUID

Standard Term

Official RFC 4122 / RFC 9562 specification
Used in most programming languages
Cross-platform standard

GUID

Microsoft Term

Common in Microsoft technologies
Used in .NET, COM, Windows
Same format as UUID

Why choose UUID v7 over v4 for databases?

UUID v7 embeds a millisecond-precision timestamp, making values naturally sorted by creation time. This provides significant performance benefits for database operations:

Improved B-tree index performance — Sequential inserts reduce page splits
Better cache utilization — Recently inserted data stays in hot pages
Efficient range queries — Time-based queries use index ordering
No separate timestamp column needed — Creation time is embedded in the ID

Best Practice: Use UUID v7 for database primary keys in high-volume applications where insertion order and query performance matter.

Is this tool secure?

Yes, absolutely. All UUIDs are generated entirely in your browser using the Web Crypto API, which provides cryptographically secure random number generation.

Client-side generation — Uses crypto.randomUUID() and crypto.getRandomValues()
No server communication — Nothing is sent to any server
No data storage — UUIDs are not logged or saved anywhere
Cryptographically secure — Uses browser's native secure random generator

Privacy Guarantee: Your generated UUIDs are completely private. They exist only in your browser and are never transmitted or stored externally.