ClassicUO Web lets you jump into Ultima Online directly from your browser — no installer, no launcher, and no manual file management. This guide walks you through everything from system requirements to your first login.Documentation Index
Fetch the complete documentation index at: https://mintlify.com/ClassicUO/classicuo-web/llms.txt
Use this file to discover all available pages before exploring further.
System Requirements
Before you begin, make sure your setup meets these requirements:- Browser: Google Chrome or any Chromium-based browser (e.g. Edge, Brave, Opera). Firefox and Safari are not supported.
- Disk space: Approximately 3.2 GB of free storage for the browser’s Origin Private File System cache.
- Internet connection: A stable broadband connection. First-time downloads are larger; subsequent launches use cached files.
ClassicUO Web relies on APIs that are only available in Chrome and Chromium-based browsers. If you’re on Firefox or Safari, you’ll need to switch browsers before continuing.
Play on Free Shards
Use play.classicuo.org to browse the community server list and join any free-to-play shard.Open a Chromium-based browser
Launch Google Chrome, Microsoft Edge, Brave, or another Chromium-based browser. Make sure it is up to date for the best compatibility.
Visit play.classicuo.org
Navigate to play.classicuo.org. You’ll land on the ClassicUO Web server list, where available shards are displayed.
Log in with Discord
Click the Sign in with Discord button. Discord authentication keeps the service secure, prevents abuse, and syncs your macros, scripts, and hotkeys across devices. You will only need to authorise once.
Pick a shard
Browse the server list and click on a shard that interests you. Each listing shows a description, player count, and other details to help you choose.
Wait for the initial download
The first time you play, the client will fetch and cache the game files needed for that shard. This typically takes a few minutes depending on your internet speed. Progress is shown on-screen. Subsequent launches are much faster as files are already cached locally.
Play on Official Ultima Online Servers (Retail)
ClassicUO Web has been sanctioned for use on the official Ultima Online servers managed by Broadsword. Visit retail.classicuo.org to access the retail version of the client.Some Web Assistant features are restricted on official servers at Broadsword’s request. See the Retail FAQ for a full breakdown of what is and isn’t available.
Storage & Caching
Game files are stored inside your browser’s local storage using the Origin Private File System. You can view current disk usage by clicking the profile icon at the top right of the side menu inside the client. If you need to free up space, you can clear the storage from the same menu — note that this will require the files to be re-downloaded on your next session.What’s Next?
Player FAQ
Answers to the most common questions about Discord login, performance, multiple accounts, and more.
Retail FAQ
Playing on official Ultima Online servers? Find out what features are available and how the sanctioned client works.
Features
Explore the Web Assistant features — game profiles, hotkeys, auto-loot, grid containers, and more.
Troubleshooting
Having issues? Check the troubleshooting guides for fixes covering performance, storage, and browser setup.