---
id: duplicates.what-is-auto-scan-in-duplicates
url: https://storagestudio.us/faq/duplicates/what-is-auto-scan-in-duplicates
category: "Duplicate files"
subcategory: "Scanning and Auto-scan"
question: "What is Auto-scan in the Duplicates window?"
alt_questions:
  - "Does Storage Studio look for duplicates in the background?"
  - "How does automatic duplicate scanning work?"
  - "Is Auto-scan on by default?"
  - "When does the background duplicate scan run?"
  - "duplicates auto scan storage studio"
  - "Does it check for duplicates automatically?"
short_answer: "Auto-scan checks a source for duplicates in the background so results are ready when you look. It's on by default per source; This Mac is only scanned when idle, plugged in and cool, cloud accounts wait for a short pause, and each runs at most once every few hours."
tags: ["duplicates", "auto-scan", "background"]
related: ["https://storagestudio.us/faq/duplicates/how-do-i-turn-off-auto-scan-for-duplicates", "https://storagestudio.us/faq/duplicates/why-does-the-duplicate-scan-say-waiting", "https://storagestudio.us/faq/duplicates/does-duplicate-scanning-slow-down-my-mac"]
applies_to: "all"
last_reviewed: 2026-10-01
---

# What is Auto-scan in the Duplicates window?

**Auto-scan** lets Storage Studio check a source for duplicates quietly in the background, so results are ready when you open the window. It's on by default, and there's a separate switch for each source.

It's built to stay out of your way:

- **This Mac** is only scanned when your Mac is idle, plugged in and cool, because reading your files competes with your own work.
- **Cloud accounts** are much lighter to check — only a list of file fingerprints is read — so they just wait for a short pause in your typing, and run on battery too unless it's low.
- Background checks run one account at a time, and at most once every few hours for each source.

Results are remembered between launches, so the window opens instantly.