UUID Generator
Generate UUIDs/GUIDs right in your browser. Supports UUID v4 (random) and v7 (time-ordered), batch generation, 10 output formats, and instant copy to clipboard.
Generator
What is a UUID?
A UUID (Universally Unique Identifier), also known as GUID (Globally Unique Identifier), is a 128-bit identifier standardised in RFC 4122 and later RFC 9562. UUIDs are designed to be unique without central coordination — making them ideal for distributed systems, databases, and anywhere you need a reliable unique key.
A UUID looks like 550e8400-e29b-41d4-a716-446655440000 — 32 hexadecimal digits displayed in five groups separated by hyphens.
UUID v4 vs v7
| UUID v4 | UUID v7 | |
|---|---|---|
| Generation | Fully random | Time-ordered (millisecond Unix timestamp + random) |
| Sortability | Not sortable | Roughly sortable by generation time |
| Use case | General-purpose identifiers | Database keys, logs, event streams where ordering matters |
| Collision risk | Extremely low (122 random bits) | Extremely low |
When to use v4: You just need a random unique ID and don't care about order — session tokens, anonymous IDs, etc.
When to use v7: You need IDs that reflect creation time — database primary keys, message IDs, time-series data, etc.
Supported Output Formats
This generator supports 10 formats out of the box:
- Standard —
550e8400-e29b-41d4-a716-446655440000 - Hyphenless —
550e8400e29b41d4a716446655440000 - Braces —
{550e8400-e29b-41d4-a716-446655440000} - URN —
urn:uuid:550e8400-e29b-41d4-a716-446655440000 - ByteArray —
{ 0x55, 0x0E, 0x84, 0x00, ... } - C++ Macro —
DEFINE_GUID(name, 0x550E8400, ...) - C# Struct —
new Guid("550e8400-e29b-41d4-a716-446655440000") - Base64 — Standard Base64 encoding
- Base64URL (RFC 7515) — URL-safe Base64 (for JWT and URLs)
- URL Encoded — Base64 string with URL percent-encoding applied
FAQ
Are the generated UUIDs truly unique? UUID v4 uses 122 random bits, giving roughly 5.3 × 10³⁶ possible values. In practice, collision is astronomically unlikely — if your entire system generates a total of 100 trillion UUIDs over its lifetime, the collision probability is still roughly one in a billion. (The popular "billions per second for millions of years" claim actually underestimates the risk due to the birthday paradox, but real-world usage is nowhere near those volumes.)
Is my data sent to a server? No. All generation happens entirely in your browser using the Web Crypto API. No data is ever sent to any server.
How many UUIDs can I generate at once? Up to 1,000 per batch. Click Generate repeatedly for more.
Can I copy UUIDs in bulk? Yes. Click Copy All in the output section, or click any Format Matrix card to copy all UUIDs in that format.
Want to dive deeper? Read What Exactly Is a GUID? — Structure, Versions, and Uniqueness Explained for the full breakdown.
Need more power? QuickGUID is a native Windows GUID toolbox with batch generation, smart extraction from logs, and 10+ format live conversion — completely free and offline.