RFC 4122 & RFC 9562 UUID / GUID Generator

Our RFC 4122 & RFC 9562 UUID/GUID Suite generates cryptographically secure, collision-resistant unique identifiers entirely on your local machine using hardware entropy from the native Web Crypto API (SubtleCrypto & CSPRNG). Supporting both UUID Version 4 (Pseudorandom) and the modern UUID Version 7 (Time-Ordered Monotonic), it satisfies high-throughput database primary key requirements and enterprise distributed microservice tracing without server telemetry.

Mathematical Architecture & RFC 9562 Specifications

A standard UUID is a 128-bit unsigned integer represented as a 36-character hexadecimal string divided into five hyphenated segments: 8-4-4-4-12.

• UUID Version 4 (Random): Encodes 122 bits of pure cryptographic entropy from CSPRNG, with 6 bits reserved for Version (0100) and Variant 1 (10). The total number of unique v4 UUIDs is 2^122 (~5.316 x 10^36). Collisions are mathematically negligible.
• UUID Version 7 (Unix Epoch Time-Ordered): Standardized in RFC 9562 (2024), UUIDv7 embeds a 48-bit big-endian millisecond timestamp in the highest bits, followed by 74 bits of entropy. Because UUIDv7 values are naturally monotonic (chronologically sortable), they eliminate B-Tree index fragmentation and random disk I/O in transactional databases (PostgreSQL, MySQL InnoDB, ClickHouse).

Definitive UUID Version Comparison: v1 vs v3 vs v4 vs v5 vs v7

Developer Implementation Code Snippets

Node.js & TypeScript

export function createTraceId(): string {
  return crypto.randomUUID(); // Native v4 in Node 19+ and browsers
}

Python 3

import uuid
v4_id = uuid.uuid4()
print("UUID v4:", str(v4_id))
print("32-char Hex:", v4_id.hex)

Go

package main
import "github.com/google/uuid"

func main() {
	id, _ := uuid.NewRandom() // v4
	idV7, _ := uuid.NewV7()    // v7 Time-Ordered
}