Why disk storage of my Mac is always full? 📀

MJ Studio
MJ Studio
Published in
4 min readApr 24, 2020


Hi, I am a mobile application developer using Macbook Pro 2018. I didn’t add any options to my Macbook so my storage is only 256GB SSD😅. Are you understanding the concept of storage? 256GB is not a small capacity.

1Gigabyte = 1,000Megabyte = 1,000,000Kilobyte = 1,000,000,000Byte

Why 1GB == 1,000MB instead of 1,024MB? I think it doesn’t matter. Read this 😁

But we always feeling our Macintosh HD doesn’t have enough space to store our Movie, Application, Pictures, Cloud drive synchronization, etc… What makes annoy us? That is pop up like this

Ok, we percept the fact that we need to clear our storage for enough space. We generally click Manage… button. Then what can we see?

What is Documents

We can see a number of sections indicating file type. There is a kind of type like Documents, Apps, System, Others. If you clicked Manage… button in the above dialog again, then you can see like this window.

I highlighted the section in the above window. There is four sections.

  1. Large Files section indicates literally files having the big capacity in your disk. The files in this section are normally files that you have seen. You can safely delete unused files happily.
  2. Downloads section just means your Downloads directory.
  3. Unsupported Apps have applications that are unsupported in your mac os version. See this. It is not related to your disk storage at all.

Finally, you can see File Browser section This is more complicated but institutive.

File Browser

In File Browser, you can check what files are occupying heavily your disk space. I deleted 2 types of files and save my disk space dramatically.

Unused files

Did you see that? My iOS simulator requires disk space more than 30GB. But I am not using devices installed in my Mac. I deleted CoreSimulator directory. After that, I launched my simulator again for re-creation Simulator directory.

Wow. The entire development process was using only 350MB. But before, the simulator directory was 30GB! It is not necessary.

Yeah, 😁 I just retrieved my 30GB disk storage from unused files. I am a developer. In the development world, the tools are occupying too large disk space for caching data and SDK itself.

Application Data, Caches

There are so many applications in mac. In each application, the need to use your disk space for permanent data saving like shopping cart(not managed by server), contact list, etc… They store their data to your disk at the moment we don’t know. For example, I love mac os application Monosnap Monosnap is simple and flexible screen capture, video capture util for mac user(It is not AD 😅). I use Monosnap for sharing simple snap videos to my team workspace. I didn’t know the way that caches are managed in Monosnap before! (Because, I am not developer of Monosnap). I can find Monosnap cache in my File Browser section like the following.

all .mp4 files are saved locally even if I never need these files again ❗️I could safely remove these files for my disk space. You can find your own application’s cache or data in File Brower and safely delete them.


We did a short trip to manage disk storage in Mac OS. There have been so many huge files in our disk we didn’t know. The harmfulness is that if we are didn’t know about that, then we should buy a new MacBook for large storage or go to the apple store center and upgrade SSD (So expensive 💰)! Let’s clear our disk from unnecessary files and save our money!

Saving disk is Saving Money