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UUID Generator

Generate RFC-compliant UUID v4 (cryptographically random) and modern UUID v7 (time-ordered) identifiers directly in your browser. Generate up to 100 UUIDs at once with uppercase and hyphen-removal options. Powered by Web Crypto.

Generated UUIDv4 Identifiers (5)RFC 4122 cryptographically secure
1f21accd3-75fa-47f2-96ce-1aa36ca43b2d
25215a8dc-14bf-424c-a552-f16cee763252
306e76c82-a29a-460d-9a03-2b3839d55d12
4419d0438-9d3b-47bb-bca9-ecfb5b0ee958
59630db60-b87e-4a8f-bc88-26d74c8dabe0

Cryptographically Secure Random and Time-Ordered UUIDs

Universally Unique Identifiers (UUIDs) are standard 128-bit numbers used to identify information in distributed computing systems without central coordination.

UUID v4 relies on 122 bits of cryptographic randomness, providing practically zero collision probability across trillions of generated IDs.

Why UUID v7 is the Future for Databases

Standard UUID v4 causes index fragmentation and performance degradation in relational databases (PostgreSQL, MySQL) and search engines due to random insertion locations.

RFC 9562 introduced UUID v7, which encodes a 48-bit Unix epoch millisecond timestamp at the beginning of the identifier. This enables chronological sorting, faster queries, and compact sequential storage.

How to use this tool

  1. Choose between UUID v4 (random) and UUID v7 (timestamp-ordered, RFC 9562).
  2. Select the desired quantity from 1 to 100 using the input or quick preset buttons.
  3. Toggle uppercase format or remove hyphens according to your database requirements.
  4. Click Copy All to copy the entire batch or copy individual IDs with a single click.

Examples

UUID v4 random and UUID v7 time-ordered examples.

UUID v4 (Random)

crypto.randomUUID()

Format
xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
Entropy
122 bits of cryptographic randomness

UUID v7 (Time-Ordered)

RFC 9562 Timestamp-ordered

Prefix
48-bit Unix epoch millisecond timestamp
Database Advantage
Sequential B-Tree insert clustering

Frequently Asked Questions

What is the difference between UUID v4 and UUID v7?
UUID v4 is entirely random (122 random bits). UUID v7 combines a 48-bit Unix millisecond timestamp with random bits, making it sortable by time and significantly improving database B-tree indexing performance.
Are the generated UUIDs cryptographically secure?
Yes. Both versions use the browser Web Crypto API (crypto.getRandomValues and crypto.randomUUID), providing cryptographically secure pseudo-random entropy.
What is the format of a standard UUID?
A standard UUID is a 128-bit label formatted as 32 hexadecimal digits separated into five hyphen-delimited groups: 8-4-4-4-12 (total 36 characters).
Can I generate UUIDs without hyphens for compact storage?
Yes. Enable the No Hyphens checkbox to generate 32-character continuous hex strings ideal for MongoDB ObjectId replacements or compact database columns.
Can I generate up to 100 UUIDs in a single batch?
Yes. You can select presets for 1, 5, 10, 25, 50, or 100 UUIDs, and copy the whole list separated by newlines.

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