An Obsidian vault is plain text, so what is using the space is everything else
Notes are tiny. Attachments, the workspace cache, plugins and file history are not. How to find which part of a vault is actually large.
A vault of ten thousand notes is usually smaller than one screen recording. That is worth saying first, because people arrive at this question assuming their writing is the problem, and it almost never is.
Split the vault by what is in it
cd ~/path/to/vault
du -sh .obsidian * 2>/dev/null | sort -h | tail -10
find . -name '*.md' -exec du -ch {} + 2>/dev/null | tail -1The last line totals the markdown alone. Compare it against the whole vault and the difference is attachments, plugins and cache, in that order of likelihood.
What is inside .obsidian
| Item | What it is | Safe to remove |
|---|---|---|
plugins | Community plugins, some with binaries | Uninstall through the app |
workspace.json | Open panes and layout | Yes, resets the layout |
cache | Search and link index | Yes, rebuilt on open |
| File recovery snapshots | Periodic copies of edited notes | Yes, you lose local version history |
File recovery is the surprise
The built in file recovery plugin keeps periodic snapshots of every note you edit, and on a vault edited daily for a year that database is far larger than the notes themselves. Its settings include how often snapshots are taken and how long they are kept, and both default to generous.
Attachments
find . -type f ! -name '*.md' -size +5M -exec ls -lh {} + 2>/dev/null \
| sort -k5 -h | tail -15Images pasted from a clipboard, PDFs dropped in for reference, and the occasional video are what fill a vault. Setting a single attachments folder in the app's settings makes them countable rather than scattered, which is worth doing before the vault gets large.
If the vault is in a sync folder
A vault inside Dropbox, iCloud Drive or a similar service is stored locally in full by default, and the version history that service keeps is on top of the version history the vault keeps. What sync folders keep locally covers making that on demand instead.
Common questions
Why is my Obsidian vault so large?
Almost never the notes. Attachments such as pasted images, PDFs and video are usually the bulk, followed by file recovery snapshots and plugins with bundled binaries.
Can I delete the .obsidian folder?
Not wholesale, since it holds your plugin configuration and layout. The cache inside it is safe to remove and is rebuilt when the vault opens, and file recovery snapshots can be cleared from the plugin's settings.
What is taking up space in Obsidian's file recovery?
Periodic snapshots of every note you edit, kept for a configurable period. On a vault edited daily for a year the snapshot database can be much larger than the notes themselves.
How do I find large attachments in a vault?
Use find inside the vault folder for non markdown files over a few megabytes and sort by size. Setting a single attachments folder in Obsidian's settings keeps them together for next time.