Zim File Format (.zim)

A Zim file holds a page from Zim, a desktop wiki application that keeps a personal note collection as plain text files marked up with Zim's own lightweight wiki syntax.

.zimDocuments

Zim at a glance#

Full name	Zim desktop wiki markup
File extension	.zim
Category	Documents
Developer	Jaap Karssenberg
Compression	Uncompressed
Specification	Zim Wiki Syntax reference
FileFlip support	FileFlip writes this format but cannot open one

What a .zim file can hold#

These are the things a Zim file either supports or does not, and they are what decides whether a conversion keeps everything or quietly drops something.

Selectable text	Yes
Human readable	Yes

Strengths and limitations of Zim#

What Zim does well

Interactive checkboxes, [ ], [*] and [x], turn a page into a working task list with no plugin needed
Every page is a plain text file in an ordinary folder tree, so a notebook works fine with Git or any file-sync tool
Zim remains under active development, with stable releases still shipping regularly

Where Zim falls short

The markup is Zim's own mix of DokuWiki and Markdown conventions, so no other wiki or editor renders it correctly
Zim itself saves pages with a .txt extension, not .zim, so the .zim extension only shows up once a page has been exported or converted
Formatting depends on Zim's own parser; a generic Markdown viewer misreads Zim's double-underscore bold and double-slash italics

Keep notes in Zim markup while they're edited inside the Zim desktop wiki, where the plain text files stay easy to back up and version.

Convert Zim pages to Markdown when notes need to move to a different note-taking app or get published somewhere Zim's syntax won't render.

How to open a .zim file#

A .zim file opens in the programs below, grouped by the platform you are on.

Platform	Programs that open it
Windows	Zim, Any text editor
macOS	Zim, Any text editor
Linux	Zim, Any text editor

Zim questions people ask#

What is a .zim file?

A .zim file holds a page's worth of Zim's wiki markup, the syntax the Zim desktop wiki uses for notes. Zim itself actually saves each page as a plain .txt file inside a notebook folder, so a .zim file is what you get once that page has been exported or converted rather than opened straight from a Zim notebook.

Where does Zim actually store my notes?

Zim keeps every page as a plain text file inside a folder tree that mirrors the notebook's page hierarchy, with the Zim wiki markup written directly into each .txt file. That's what makes a Zim notebook straightforward to back up, sync or put under version control.

Is Zim markup the same as Markdown?

No. Zim's syntax is its own, closer to DokuWiki than Markdown, using conventions like __bold__ and //italic// instead of Markdown's asterisks and underscores, so a Zim page doesn't render correctly in a generic Markdown viewer.

Converting Zim files#

FileFlip cannot open a .zim file, so there is nothing to convert it into here. It appears on the site as something other formats can be converted to.

Every conversion runs inside your browser. The file is read from your disk, the work happens on your own machine, and nothing is uploaded. How FileFlip works names the engine behind each family and how to verify that for yourself.