Inode
Inode is an information storage unit in the Linux file system that records the technical data of a file — such as its size, date created, access permissions, and its physical location on the server.
Every file and folder on your hosting uses one inode, regardless of how small its size.
Simple analogy
Imagine a large library. Each book has a catalog card that records the title, author, shelf where the book is stored, and the date it was last borrowed. Inodes are those catalog cards — not the contents of the book, but information about the book.
Libraries can run out of catalog cards even though they still have plenty of empty shelf space. The same thing can happen to your hosting.
Why are Inodes Important in Hosting?
Shared hosting providers almost always limit the number of inodes per account — generally between 50,000 to 250,000 inodes.The limit is not in file size, but in number of files and folders. This means that you can run out of inodes even though you still have a lot of disk quota remaining. When the inode limit is reached, you cannot create new files — including incoming emails, caches, or uploads — until an inode is freed.
What Eats the Most Inodes?
| Source | Description |
|---|---|
| Each email = 1 inode. Inbox thousands of emails = thousands of used inodes | |
| CMS Cache WordPress, Joomla and | the like generate lots of small cache files |
| Session files Uncleaned PHP session files accumulate in | the /tmp folder |
| Local backup Backups stored on | the server itself can contain hundreds of thousands of files |
| Node modules | The node_modules folder can notoriously contain tens of thousands of files at once |
How to Check Inode Usage
In cPanel, you can see it directly on the main page — usually displayed alongside disk usage.
Over SSH, run this command to see the inodes used per folder:
bash
find . -maxdepth 1 -type d | xargs -I{} sh -c 'echo "$(find {} | wc -l) {}"' | sort -rn | head -20
The results will show which folders are consuming the most inodes — useful for quickly finding the source of the problem.
What You Need to Pay Attention to
- Routinely clean old email — Especially if email hosting is actively used. Archive or delete emails that you no longer need regularly.
- Don't store backups on the server — Local backups within a hosting account are an often overlooked inode eater. Use external storage or a separate backup service.
- Limit cache retention — Make sure the cache plugin in your CMS has an auto-purge setting so that old files don't accumulate.
- Pay attention to inode limits when choosing hosting — Some hosts do not list this number transparently. Ask directly, or check the package specifications page.
FAQs
Do inodes matter on a VPS or dedicated server? Technically there are, but the inode limits on VPS and dedicated servers are usually much higher — they may not even be limited at all. Inode issues arise most often in shared hosting.
My inodes are almost full, what should I do? First, find the folder with the most inodes using the command above. Usually the main suspects are email, cache, or session files. Clean it from there first before contacting hosting support.
Does deleting large files automatically free up a lot of inodes? Not always. One large file only uses 1 inode, the same as one small file. What is more effective is deleting folders containing thousands of small files.
Disclaimer: Hosting Wiki articles are prepared for educational and reference purposes. Hosting technology keeps evolving, so some technical details may change over time.