---
id: external-drives.why-are-many-small-files-slow-to-copy
url: https://storagestudio.us/faq/external-drives/why-are-many-small-files-slow-to-copy
category: "External drives"
subcategory: "Speed, cables and hardware"
question: "Why is copying lots of small files so much slower than one big file?"
alt_questions:
  - "Copying many small files slow Mac"
  - "Why does copying node_modules take forever?"
  - "Finder slow copying folder with thousands of files"
  - "small files transfer speed external drive"
short_answer: "Each file has a fixed cost to create and close, so thousands of tiny files spend most of the copy on overhead. Delete rebuildable caches instead of copying them, and compress a folder into one file for archiving."
tags: ["small files", "copy speed", "performance"]
related: ["https://storagestudio.us/faq/external-drives/why-is-my-external-ssd-slower-than-advertised", "https://storagestudio.us/faq/external-drives/why-does-copy-speed-drop-partway", "https://storagestudio.us/faq/external-drives/does-a-moved-folder-take-the-same-space-on-the-drive"]
applies_to: "all"
last_reviewed: 2026-10-01
---

# Why is copying lots of small files so much slower than one big file?

Every file has a fixed cost — creating it, writing its details and closing it — no matter how small it is. A folder of tens of thousands of tiny files spends most of its time on that overhead, so it moves far more slowly than one big file of the same total size. This affects every drive and every app.

What helps:

- Delete what you can rebuild (caches, build folders) instead of copying it.
- For an archive, compress the folder into one file first.
- Expect large code or photo-thumbnail folders to take longer than their size suggests.

Storage Studio checks a move against the original before it removes anything, so folders with huge numbers of small files take longer than their size alone suggests — let them run.