Building Your Unity 2021 Project for itch.io

The first thing you’ll want to do is set the Compression Format to “Gzip” in Project Settings > Player before building to WebGL.

Beyond the standard limitation of 1GB for overall project files, itch.io has some additional restrictions specifically for WebGL deployments.

In reality, you now have a 500MB limit for your project files and no single file can be over 200MB.

That second part can really cause some headaches.

The main file that tends to run over 200MB is the WebGL.data file in your build folder for WebGL.

Nine times out of ten, the culprit will be your textures files!

But to find out for sure, run your build and then click the show editor log from the console window as shown above.

We can do a few things directly in our build settings to minimize our file size.
Max texture size will likely have the largest impact.
Unfortunately, the lower your texture size, the worse your textures look.

As tedious as it is, the best approach to reduce texture size is to make that determination at the individual file level.

By observing the changes you make to the “Max Size” import setting for each texture in your scene or game view, you can dial these in.

Generally, reserve higher sizes for textures that will be frequently viewable up close or when forced to due to obvious quality degradation during gameplay.

Also, note that the preview window will list the actual file size at the selected “Max Size” for the selected texture.

.7MB doesn’t sound like a lot unless you have 100 more (70MB)…

In this day and age, anything that doesn’t add up to the Gigabytes seems small to us but that just isn’t the case with WebGL deployments due to browser and bandwidth limitations.

Another import setting that can be used is called “Crunch Compression”.

I have to say I was not impressed with the Quality set at 50, but play around with this value and with the right texture use-case, this could come in handy.

I’d recommend using it for textures that will be deep in the background or occupy very little screen space.

At the end of the day, some projects will be just to big for WebGL.

Fortunately, itch.io also allows Windows/iOS builds that are downloaded to the users machine.

These projects are limited to an overall size of 1GB though.

I recommend downloading and installing the itch.io app as it will show your unpublished creations and makes it easy to install or update your games from the end-user perspective.

If your game shows an error similar to that shown above on itch.io’s website, you’ll need to change your Player Settings.

In Project Settings > Player > WebGL > Publishing Settings, set the “Compression Format” to “Disabled”.