discussion Why no compression?

[restboi]

Hi,

I have never built own game, but was thinking of it. i have genuine question, why do so many game publishers not compress by default? i mean not lossy, but just with higher 7z preset or zip preset? is there some reasoning behind it? i often open zip and see size of game is same as zip. is this some marketting tactic? to show the game actually has stuff in it. i do not know much about game dev so it is why i ask here. is there some pitfall waiting for me if i want to make game and compress?

 

[Rimuru12]

Compressing a game is complicated. some people just dont want to risk losing data through compression. many newer game devs also dont think about compressing files and just view zip as a convenient way to sent files

 

[misterfluffums]

The size of games is mainly due to images and movies, which are hard to compress with a generic algorithm like zip. Have you tried repacking the zips to see how much space you can save? It'll disappoint you.

Why the images geney aren't compressed is the desire to deliver as high quality as possible overriding rationality. I only started to lossy compress the images when I found I really couldn't tell the difference with png.

Of course I saved the original assets without compression somewhere just in case I ever decide to up the resolution of my game or something.

 

[Republican Bear]

Developers use to compress games because of console and hardware limitations.

Now they still compress but not as much, and it helps to deter pirating when your game is over 150+ GB.

TLDR- Developers still compress games but as much as it's not needed anymore.

 

[SilentHunter]

I believe 2 factors play a role. 1. The problem of free space on current HDDs has long lost its importance (I'm sorry for the owners of mobile devices, but these are their problems, build or buy a normal desktop with the ability to install 3-4 HDDs). 2. Some developers persist in using the .png format, which leads to an anecdotal increase in the volume of ordinary visual novels.
And finally, I will add my personal comment. I never download compressed games, because compression artifacts are very annoying on a UHD monitor in full-screen mode.

Post automatically merged: Mar 6, 2026

Compressing a game is complicated. some people just dont want to risk losing data through compression. many newer game devs also dont think about compressing files and just view zip as a convenient way to sent files

A comprehensive answer to the question about the reason for using archives. Basic convenience when uploading/downloading files.

 

[PliminJET]

Developers use to compress games because of console and hardware limitations.

Now they still compress but not as much, and it helps to deter pirating when your game is over 150+ GB.

TLDR- Developers still compress games but as much as it's not needed anymore.

Compressing doesn't deter pirating.

For the question: the answer has been previously mentioned, devs don't compress because they just don't know from inexperience, or they're lazy and it's more work.. list goes on. But it's not just simply press a magic button and now you have smaller files.

First, why does compression even exist? Why don't file formats just already be as minimal as possible from the get go???

It's because compression doesn't care about file format. It's an algorithm working on raw numbers. Compression's goal is to group those numbers into recognizable patterns as fast as possible while allowing reconstruction. The algorithms vary. There are lossy and lossless algorithms plus a myriad in-between. The lossy algorithms work on blast file formats that don't need to be reconstructed perfectly, such as images. You can mix up a few bytes in an image and you'll still see the same thing, it doesn't matter. So when it compresses the image, some bytes can be replaced with the wind when you reverse the algorithm (decompress), just the name of the game. But too many bytes lost make the images have artifacts, or lose brightness, or decrease the color range depending on the algorithm. There're trade-offs. Devs have to manually compress based on their file formats which is daunting.

I'm not sure what RenPy is capable of for compression but I imagine it's probably not the most optimal by default. Devs have to go out of their way to do actual fine grained optimization in RenPy which just isn't what a non-programmer knows how, or wants, or needs to do. VN devs are normally artists and story tellers, not programmers.

 

[Redyscom]

When I have to update large games, I split them into parts and, in addition to the full game, upload the parts so people can download them using different servers and avoid getting stuck with download limits like the ones on Mega and Pixeldrain.

But it’s not something I enjoy doing—it takes a lot of time.
I have to download the game, which usually takes a while if it’s big, then split it up, which also takes time, and then I have to set up at least 4 mirrors for each part. I usually split it into 3 parts of 5 GB each, so that means 12 uploads. If the game also has Win/Linux, Mac, and Android versions, then that’s 36 uploads I have to do for a single game.

It would be much easier if the devs or others did the compression, but as someone else said, you risk data loss, corruption, or the process getting cut off halfway through and everything going to hell.



I’d like to say“If you see a really big game that isn’t compressed or split into parts, let me know and I’ll split it up and post the links in the thread” but that’s not realistic—I’d only do that for full games, because having to do it with every update would be a nightmare.

 

[xpop49]

Then there is also the risk on someone sneaking malware into the zip files

Goes undetected in transport

Only comes up when you unzip

So basically a carrier