UUID / ULID Generator Pro

Generate UUID v4 and ULID identifiers, in bulk, with real cryptographic randomness — fast, private, and fully offline.

A premium, zero-dependency ID workbench. Switch between RFC 4122 UUID v4 (native crypto.randomUUID(), or an included manual implementation) and a from-scratch, spec-correct ULID generator. Generate up to 1000 at once, reformat instantly, and export — all in your browser, with nothing ever leaving your machine.

Overview

UUID / ULID Generator Pro is part of the Web Utility Suite. It runs entirely in the browser with no build step, no frameworks, and no network calls — open index.html from disk and it works. Pick an ID type, set a count, and generate. Every ID in the results list gets its own copy button, and the whole batch can be copied or downloaded as a .txt file in one click.

Features

• UUID v4 — uses the browser's native crypto.randomUUID() by default. Also ships a real, from-scratch manual RFC 4122 v4 implementation (crypto.getRandomValues + correct version/variant bit masking) that's used automatically when crypto.randomUUID isn't available, and can be forced on for educational inspection.
• ULID — a genuine, from-scratch pure-JS implementation of the ULID spec: a 48-bit millisecond timestamp encoded as the first 10 characters plus 80 bits of crypto.getRandomValues entropy encoded as the last 16 characters, both in Crockford's Base32 (excludes I, L, O, U) — 26 characters total, lexicographically sortable by creation time.
• Bulk generation — generate 1 to 1000 IDs in a single click; count is validated and clamped.
• Live format toggles (UUID only) — with/without hyphens, uppercase/lowercase, wrapped in {braces}. Toggling reformats the current batch instantly, no regeneration needed.
• Per-ID copy buttons plus Copy all and Download as .txt for the whole batch.
• Cryptographically strong throughout — every ID's randomness comes from crypto.getRandomValues() / crypto.randomUUID(); Math.random() is never used for ID generation.
• Auto-persisted settings — your last mode and toggle choices are saved to localStorage and restored on return.
• Dark & light themes, fully responsive down to 360px, accessible, and keyboard-driven.

Installation

No dependencies, no build step.

git clone https://github.com/kasapdev/uuid-generator-pro.git
cd uuid-generator-pro

Then simply open index.html in any modern browser (double-click it, or file:// it). That's it.

Usage

1. Choose UUID v4 or ULID from the segmented control.
2. Set Count (1–1000) and click Generate (or press Ctrl/⌘+Enter).
3. For UUID v4, optionally enable Manual RFC4122 v4 to use the hand-rolled implementation instead of crypto.randomUUID(), and flip Hyphens, Uppercase, or Braces to reformat the batch live.
4. Copy an individual ID with its row button, or use Copy all / Download .txt for the whole batch.

Keyboard Shortcuts

Action	Shortcut
Generate	Ctrl/⌘ + Enter
Download as .txt	Ctrl/⌘ + S
Show shortcuts help	?
Close dialog	Esc

Screenshots

Screenshots coming soon.

Roadmap

• UUID v1 / v5 (namespace-based) generation
• NIL and Max UUID constants as quick-insert options
• Batch validation / parsing of pasted IDs (detect type, check structure)
• QR code export for a single generated ID

License

MIT Licensed. Part of the Web Utility Suite.