Exporting for the Web¶
HTML5 export allows publishing games made in Godot Engine to the browser. This requires support for the recent technologies WebAssembly and WebGL 2.0 in the user’s browser. Firefox and Chromium (Chrome, Opera) are the most popular supported browsers, Safari and Edge do not work yet. On iOS, all browsers must be based on WebKit (i.e. Safari), so they will also not work.
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.
.html file must not be reused¶
On export, several text placeholders are replaced in the generated HTML file specifically for the given export options. It must not be reused in further exports.
Full screen and mouse capture¶
Browsers do not allow arbitrarily entering full screen at any time. The same
goes for capturing the cursor. Instead, these actions have to occur as a
entering full screen from within an input callback such as
For the same reason, the full screen project setting is ignored.
HTTPClient implementation for the HTML5 platform has several
- Accessing or changing the
StreamPeeris not possible
- 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
- Subject to same-origin policy
The following functionality is currently unavailable on the HTML5 platform:
- Clipboard synchronisation between engine and operating system
- Networking other than
Check the list of open HTML5 issues on Github to see if functionality you’re interested in has an issue yet. If not, open one to communicate your interest.
Starting exported games from the local file system¶
Many browsers, Chromium-based browsers specifically, will not load exported
projects when opened locally per
file:// protocol. To get around this,
use a local server.
Python offers an easy method for this, using
python -m SimpleHTTPServer
with Python 2 or
python -m http.server with Python 3 will serve the current
working directory on
Serving the files¶
Exporting for the web generates several files to be served from a web server, including a default HTML page for presentation. A custom HTML file can be used, see Customizing the Web export HTML page.
.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.
The HTML page is designed to fit the game perfectly without cutting off
parts of the canvas when the browser window is scaled to the game’s dimensions.
This way it can be inserted into an
<iframe> with the game’s size, as is
common on most web game hosting sites.
The other exported files are served as they are, next to the
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
.wasm file is delivered as
Delivering the files with server-side compression is recommended especially for
.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.
If a runnable web export template is available, a button appears between the Stop scene and Play edited Scene buttons in the editor to quickly open the game in the default browser for testing.
If a path to a Custom HTML shell file is given, it will be used instead of the default HTML page. See Customizing the Web export HTML page.
Head Include is appended into the
<head> element of the generated
HTML page. This allows to, for example, load webfonts and third-party
In web builds, the
This allows interacting with the browser in ways not possible with script
languages integrated into Godot.
eval() under certain circumstances:
HTML5 export templates may be built without support for the singleton. With such
templates, and on platforms other than HTML5, calling
null. The availability of the singleton can be checked with the
eval method also accepts a second, optional Boolean argument, which
specifies whether to execute the code in the global execution context,
false to prevent polluting the global namespace: