---
id: freeing-space.which-app-is-filling-my-disk
url: https://storagestudio.us/faq/freeing-space/which-app-is-filling-my-disk
category: "Freeing up space"
subcategory: "Where your space went"
question: "How does Storage Studio work out which app is using up my disk space?"
alt_questions:
  - "Which app is using all my space?"
  - "Who is writing all these files?"
  - "Find the app eating my storage"
  - "Storage Studio names the app"
  - "Why does the notice say it couldn't tell?"
short_answer: "It traces where new data went and names the app when it can identify one, hedges when it only looks likely, and says plainly when it couldn't tell. It never invents a name."
tags: ["space watch", "apps", "attribution"]
related: ["https://storagestudio.us/faq/freeing-space/can-i-stop-one-app-filling-my-disk", "https://storagestudio.us/faq/freeing-space/how-do-i-silence-notices-about-an-expected-app"]
applies_to: "all"
last_reviewed: 2026-10-01
---

# How does Storage Studio work out which app is using up my disk space?

When free space starts dropping, Storage Studio works out where the new data went and matches it to an app when it can. It's careful about how sure it is:

- it **names** the app when it can identify one,
- it **hedges** when a folder only looks like it belongs to an app,
- it **says plainly** when it couldn't tell — it never invents a name.

Anything that can't be accounted for is shown as its own line rather than spread across the rest. You can see the same breakdown under the storage chart at any time. See [Can I stop one app from filling my disk?](https://storagestudio.us/faq/freeing-space/can-i-stop-one-app-filling-my-disk)