uuidv7

Generate UUID v7 strings, like 019212d3-87f4-7d25-902e-b8d39fe07f08.

uuidv7 > uuidv7.txt

019212d3-87f4-7d25-902e-b8d39fe07f08

| 32-bit time | 16-bit time | 4 ver + 12 rnd | 2 var + 14 rnd | 16 rnd + 32 rnd | | :------------------------: | :---------: | :------------: | :------------: | :----------------------------------------: | | 01 92 12 d3 | 87 f4 | 7d 25 | 90 2e | b8 d3 9f e0 7f 08 |

Table of Contents

• Install
• In JavaScript
• UUIDv7 Spec
  • By the Characters
  • By the Bits
• Zig Build
• License

Install

Pre-built archives available for Mac, Linux, & Widows.
Compile from source for FreeBSD, OpenBSD, etc.

1. Download from GitHub Releases: https://github.com/coolaj86/uuidv7/releases
2. Extract
3. Place in your PATH

b_triplet='x86_64-linux-musl'
curl -L -O https://github.com/coolaj86/uuidv7/releases/download/v1.0.0/uuidv7-v1.0.0-"$b_triplet".tar.gz
tar xvf ./uuidv7-v1.0.0-"$b_triplet".tar.gz
mv ./uuidv7 ~/bin/

JavaScript Version

Supports both import and require.

Extremely simple implementation that can be tuned for speed or memory efficiency.

npm install --save @root/uuidv7

High-level API:

import UUIDv7 from "@root/uuidv7";

let buffer = new Uint8Array(4096); // optional, if you need lots of UUIDs, and fast
UUIDv7.setBytesBuffer(buffer);

UUIDv7.uuidv7();
// 01922aa4-88ad-7cae-a517-a298a491d35c

UUIDv7.uuidv7Bytes();
// Uint8Array(16) [ 1, 146,  42, 176, 37, 122, 114, 189
//                 172, 240,  1, 146, 42, 176,  37, 122 ]

Low-level API:

let now = Date.now();
let ms64 = BigInt(now);
let bytes = new Uint8Array(16);
let start = 0;
globalThis.crypto.getRandomValues(bytes);

void UUIDv7.fill(bytes, start, ms64);

console.log(bytes);
// Uint8Array(16) [ 1, 146,  42, 176, 37, 122, 114, 189
//                 172, 240,  1, 146, 42, 176,  37, 122 ]

let uuidv7 = UUIDv7.format(bytes);
console.log(uuidv7);
// 01922aa4-88ad-7cae-a517-a298a491d35c

UUIDv7 Spec

By the Characters

There are 36 characters total: 32 hex (0123456789abcdef) + 4 dashes (-)

  8 time    4 time    1v + 3ra   ½v + 3½rb    12 random b
019212d3  -  87f4   -   7d25   -   902e   -   b8d39fe07f08

• 8ch hex time high
• -
• 4ch hex time low
• -
• 4ch hex version + "random a"
  • 1ch hex version: 7
  • 3ch hex "random a"
• -
• 4ch hex variant + "random b"
  • 1ch hex version: 8, 9, a, b
  • 3ch hex "random b"
• -
• 12ch hex randam a
  • 4ch hex random a
  • 8ch hex random a

By the Bits

   48 time         4ver, 12ra   2var, 14rb        random b
019212d3-87f4    -    7d25    -    902e    -    b8d39fe07f08

• 48 bits of timestamp
  • 32-bit high (minutes to years)
  • 16-bit low (seconds & milliseconds)
• 16 bits of version + random
  • 4-bit version (0b0111)
  • 12-bit random
• 64-bits variant + random
  • 2-bit variant (0b10)
  • 62-bit random

Build

See </build.sh>.

Builds with zig v0.13 and the v0.14 previews so far.

curl https://webi.sh/[email protected] | sh
source ~/.config/envman/PATH.env

zig build-exe ./uuidv7.zig -O ReleaseSmall -femit-bin="uuidv7"

for b_target in x86-linux-musl aarch64-macos-none x86_64-windows-gnu; do
    zig build-exe ./uuidv7.zig -O ReleaseSmall \
        -target "${b_target}" -femit-bin="uuidv7-${b_target}"
done

License

Copyright 2024 AJ ONeal [email protected]

This Source Code Form is subject to the terms of the Mozilla Public
License, v. 2.0. If a copy of the MPL was not distributed with this
file, You can obtain one at https://mozilla.org/MPL/2.0/.