More than baseq3

Quake 3 Mods in Your Browser

A browser match can use more than the base game. Q3JS reads the game directory advertised by a compatible server, loads its published PK3 assets, and starts ioquake3 with that mod selected.

Selected server

Competitive arena

fs_game

Base layer

baseq3

pak0.pk3pak1.pk3pak8.pk3

Mod layer

server mod

manifest.jsonmod-assets.pk3game-vm.pk3

Restore cache → fetch changes → launch mod

Format
PK3 assets
Selection
Server driven
Storage
Browser cached

Mods without a desktop installer

The server, static asset service, and browser client agree on one game directory and one safe list of files.

Discovery

Server-selected game

Q3JS reads the advertised base game and fs_game values so the browser starts with the same game directory as the server.

Delivery

Manifest-based assets

Each game directory publishes a generated manifest containing safe PK3 filenames rather than exposing arbitrary files.

Loading

Base plus mod

The client can combine base-game assets with a separate mod directory before launching the WebAssembly engine.

Return matches

Persistent cache

Downloaded packages are stored in the browser and reused when they still match the files advertised by the asset server.

How a modded match starts

There is no separate mod picker. The server selection provides the configuration.

  1. 01

    Choose a compatible server

    Select a listed server whose game information includes a supported base game or mod directory.

  2. 02

    Load the manifests

    Q3JS requests the base-game manifest and, when needed, the additional manifest for the advertised mod.

  3. 03

    Launch with fs_game

    After restoring cached files and downloading changes, the client starts ioquake3 with the server's mod selected.

Questions

Can Q3JS load Quake 3 mods?

Yes. Q3JS supports compatible PK3-based game and mod directories advertised by a server, including separate base-game and mod asset manifests.

Do I need to install a mod manually?

No desktop installation is required. When a listed server advertises a supported mod, the browser client requests the matching published assets before starting the game.

Are mod files downloaded every match?

Usually not. Compatible browsers store downloaded assets in IndexedDB and reuse files whose size still matches the published version.

Find a different arena

Browse the live list to see the maps, modes, and game variants currently offered by Q3JS servers.