Exporting for the Web

See also Compiling for the Web. WebAssembly and WebGL in the user’s browser. Important debug information like JavaScript, engine, and WebGL errors. Attention There are significant bugs when running HTML5 projects on iOS (regardless of the browser). We recommend using iOS’ native export functionality instead, as it will also result in better performance.

WebGL version

GLES2) or WebGL 2.0 (GLES3). WebGL 1.0 is the recommended option if you want your project to be supported on all browsers with the best performance. Godot’s GLES3 renderer targets high end devices, and the performance using WebGL 2.0 can be subpar. Some features are also not supported in WebGL 2.0 specifically. Safari. WebGL 2.0 support is coming in Safari 15 for macOS, and is not available yet for any iOS browser (all WebKit-based like Safari). See Can I use WebGL 2.0 for details.

Export options

Stop scene and Play edited Scene buttons in the editor to quickly open the game in the default browser for testing. Export Type to select which features will be available:

  • Regular: is the most compatible across browsers, will not support threads, nor GDNative.
  • Threads: will require the browser to support SharedArrayBuffer. See Can I use SharedArrayBuffer for details.
  • GDNative: enables GDNative support but makes the binary bigger and slower to load. VRAM compression make sure that Vram Texture Compression is enabled for the targeted platforms (enabling both For Desktop and For Mobile will result in a bigger, but more compatible export). Custom HTML shell file is given, it will be used instead of the default HTML page. See Custom HTML page for Web export. Head Include is appended into the <head> element of the generated HTML page. This allows to, for example, load webfonts and third-party JavaScript APIs, include CSS, or run JavaScript code. Important Custom HTML shell option. Warning Export types other then Regular are not yet supported by the C# version.

    Limitations

    For security and privacy reasons, many features that work effortlessly on native platforms are more complicated on the web platform. Following is a list of limitations you should be aware of when porting a Godot game to the web. Important secure contexts, this means that such features are only be available if the web page is served via a secure HTTPS connection (localhost is usually exempt from such requirement). Tip list of open HTML5 issues on GitHub to see if the functionality you’re interested in has an issue yet. If not, open one to communicate your interest.

    Using cookies for data persistence

    allow cookies (specifically IndexedDB) if persistence of the user:// file system is desired. When playing a game presented in an iframe, third-party cookies must also be enabled. Incognito/private browsing mode also prevents persistence. OS.is_userfs_persistent() can be used to check if the user:// file system is persistent, but can give false positives in some cases.

    Background processing

    _process() and _physics_process() will no longer run until the tab is made active again by the user (by switching back to the tab). This can cause networked games to disconnect if the user switches tabs for a long duration. windows. Therefore, on the user’s side, this can be worked around by running the project in a separate window instead of a separate tab.

    Threads

    above multi-threading is only available if the appropriate Export Type is set and support for it across browsers is still limited. Warning secure context. Browsers also require that the web page is served with specific cross-origin isolation headers.

    GDNative

    above GDNative is only available if the appropriate Export Type is set. .wasm files to the output folder (and must be uploaded to your server along with your game).

    Full screen and mouse capture

    entering full screen. The same goes for capturing the cursor. Instead, these actions have to occur as a response to a JavaScript input event. In Godot, this means entering full screen from within a pressed input event callback such as _input or _unhandled_input. Querying the Input singleton is not sufficient, the relevant input event must currently be active. customization of the HTML page.

    Audio

    Chrome restricts how websites may play audio. It may be necessary for the player to click or tap or press a key to enable audio. See also Web Audio autoplay policies. Warning secure context.

    Networking

    Low level networking is not implemented due to lacking support in browsers. HTTP client, HTTP requests, WebSocket (client) and WebRTC are supported. The HTTP classes also have several restrictions on the HTML5 platform:
    • StreamPeer is not possible
  • Threaded/Blocking mode is not available
  • Cannot progress more than once per frame, so polling in a loop will freeze
  • No chunked responses
  • Host verification cannot be disabled
  • same-origin policy

    Clipboard

    Clipboard API, additionally, due to the API asynchronous nature might not be reliable when accessed from GDScript. Warning secure context.

    Gamepads

    Gamepad API does not provide a reliable way to detect the gamepad information necessary to remap them based on model/vendor/OS due to privacy considerations. Warning secure context.

    Boot splash is not displayed

    custom HTML pages can display it.

    Shader language limitations

    When exporting a GLES2 project to HTML5, WebGL 1.0 will be used. WebGL 1.0 doesn’t support dynamic loops, so shaders using those won’t work there.

    Serving the files

    Custom HTML page for Web export. .html file can be used as DirectoryIndex in Apache servers and can be renamed to e.g. index.html at any time, its name is never depended on by default. <iframe> with the game’s size, as is common on most web game hosting sites. .html file, names unchanged. The .wasm file is a binary WebAssembly module implementing the engine. The .pck file is the Godot main pack containing your game. The .js file contains start-up code and is used by the .html file to access the engine. The .png file contains the boot splash image. It is not used in the default HTML page, but is included for custom HTML pages. .pck file is binary, usually delivered with the MIME-type application/octet-stream. The .wasm file is delivered as application/wasm. Caution .wasm) with a MIME-type other than application/wasm can prevent some start-up optimizations. .pck and .wasm files, which are usually large in size. The WebAssembly module compresses particularly well, down to around a quarter of its original size with gzip compression. Hosts that provide on-the-fly compression: GitHub Pages (gzip) Hosts that don’t provide on-the-fly compression: itch.io, GitLab Pages (supports manual gzip precompression)

    Calling JavaScript from script

    JavaScript singleton is implemented. It offers a single method called eval that works similarly to the JavaScript function of the same name. It takes a string as an argument and executes it as JavaScript code. This allows interacting with the browser in ways not possible with script languages integrated into Godot.
    1. func my_func():    JavaScript.eval("alert('Calling JavaScript per GDScript!');")
    eval() under certain circumstances:
    • number is returned as GDScript float
  • boolean is returned as GDScript bool
  • string is returned as GDScript String
  • ArrayBuffer, TypedArray and DataView are returned as GDScript PoolByteArray
    1. func my_func2():    var js_return = JavaScript.eval("var myNumber = 1; myNumber + 2;")    print(js_return) # prints '3.0'
    null. built without support for the singleton to improve security. With such templates, and on platforms other than HTML5, calling JavaScript.eval will also return null. The availability of the singleton can be checked with the JavaScript feature tag:
    1. func my_func3():    if OS.has_feature('JavaScript'):        JavaScript.eval("""            console.log('The JavaScript singleton is available')        """)    else:        print("The JavaScript singleton is NOT available")
    Tip """ as in my_func3() above, are useful to keep JavaScript code readable. eval method also accepts a second, optional Boolean argument, which specifies whether to execute the code in the global execution context, defaulting to false to prevent polluting the global namespace:
    1. func my_func4():    # execute in global execution context,    # thus adding a new JavaScript global variable `SomeGlobal`    JavaScript.eval("var SomeGlobal = {};", true)