HackMD is a realtime, multi-platform collaborative markdown knowledge base. You can write notes with other people on your desktop, tablet or even on the phone.
Please report new issues in GitHub. If you need instant help, please send us a Facebook message. Thank you very much!
Workspace
Modes
Desktop & Tablet
Edit: See only the editor. View: See only the result. Both: See both in split view.
Mobile
View: See only the result. Edit: See only the editor.
Image Upload:
You can upload an image simply by clicking on the camera button . Alternatively, you can drag-n-drop an image into the editor. Even pasting images is possible! This will automatically upload the image to imgur, nothing to worry.
Hint: In the private team plan, the image will be uploaded to a private S3 storage and only accessible through the note.
Share Notes:
Press the share button on the top right of the menu and click Copy button to copy the note URL link to your clipboard.
Currently, you can save to Dropbox, Google Drive, Gist or save an .md file and .html locally.
Import Notes:
Similarly to the save feature, you can also import an .md or .html file from Dropbox, Google Drive, Gist or import content from your clipboard, and that can parse some HTML which might be useful
Permissions:
It is possible to change permissions to a note through the button on the share button on the top right of the menu, click the button and you will see the Sharing menu.
For read and write permissions, you can either choose: Owners, Signed-in users or Everyone.
For commenting permission, please click More in the sharing menu and choose either: Forbidden, Owners, Signed-in users or Everyone. You even can disable the commenting feature through the toggle to the right of the commenting label.
Only the owners of the note can change above permissions.
You can use a special syntax to organize your note into slides. After that, you can use the Slide Mode to make a presentation. Visit the above link for details.
You can make your notes into a book. List your links in order or nest them. Then use the Book Mode to make a collection. Visit the above link for details.
View
Table of Contents:
You can look at the bottom right section of the view area, there is a ToC button . Pressing that button will show you a current Table of Contents, and will highlight which section you’re at. If the view area is wide enough, to ToC will show directly at the right section of the view area.
ToCs support up to three header levels.
Header link
Every header will automatically add a url link on the left side. You can hover and click to anchor on it.
Edit:
Shortcut Keys:
Just like Sublime text, which is pretty quick and convenient.
We support many programming languages, use the auto complete function to see the entire list.
var s ="JavaScript syntax highlighting";alert(s);function$initHighlight(block, cls){try{if(cls.search(/\bno\-highlight\b/)!=-1)returnprocess(block,true,0x0F)+' class=""';}catch(e){/* handle exception */}for(var i =0/2; i < classes.length; i++){if(checkCondition(classes[i])=== undefined)return/\d+[\s/]/g;}}
If you want line numbers, type = after specifying the code block languages. Also, you can specify the start line number. Like below, the line number starts from 101:
var s ="JavaScript syntax highlighting";alert(s);function$initHighlight(block, cls){try{if(cls.search(/\bno\-highlight\b/)!=-1)returnprocess(block,true,0x0F)+' class=""';}catch(e){/* handle exception */}for(var i =0/2; i < classes.length; i++){if(checkCondition(classes[i])=== undefined)return/\d+[\s/]/g;}}
Or you might want to continue the previous code block’s line number, use =+
var s ="JavaScript syntax highlighting";alert(s);
Sometimes you have a super long text without breaks. It’s time to use ! to wrap your code.
When you’re a carpenter making a beautiful chest of drawers, you’re not going to use a piece of plywood on the back.
Blockquote Tags:
Using the syntax below to specifiy your name, time and color to vary the blockquotes.
ChengHan Wu Sun, Jun 28, 2015 9:59 PM
Even support the nest blockquotes!
ChengHan Wu Sun, Jun 28, 2015 10:00 PM
Caution: this might be blocked by your browser if not using an https URL.
MathJax
You can render LaTeX mathematical expressions using MathJax, as on math.stackexchange.com, except the space after the start $ and the space before the end $ are not allowed in the inline math:
The Gamma function satisfying Γ(n)=(n−1)!∀n∈N is via the Euler integral
For block level math, please give $ and a line break before and after your math formula:
x=−b±√b2−4ac2a.
Γ(z)=∫∞0tz−1e−tdt.
More information about LaTeX mathematical expressions here.
More information about sequence diagrams syntax here. More information about flow charts syntax here. More information about graphviz syntax here More information about mermaid syntax here More information about abc syntax here More information about vega syntax here
Features
English version
中文版
日本語版
Read the complete tutorial
Introduction
HackMD is a realtime, multi-platform collaborative markdown knowledge base.
You can write notes with other people on your desktop, tablet or even on the phone.
Please report new issues in GitHub.
If you need instant help, please send us a Facebook message.
Thank you very much!
Workspace
Modes
Desktop & Tablet
Edit: See only the editor.
View: See only the result.
Both: See both in split view.
Mobile
View: See only the result.
Edit: See only the editor.
Image Upload:
You can upload an image simply by clicking on the camera button .

Alternatively, you can drag-n-drop an image into the editor. Even pasting images is possible!
This will automatically upload the image to imgur, nothing to worry.
Share Notes:
Press the share button on the top right of the menu and click Copy button to copy the note URL link to your clipboard.
To publish and customize the note URL with permalink, please read How to Publish a Note with Permalink.
Save a Note:
Currently, you can save to Dropbox , Google Drive, Gist or save an
.md
file and.html
locally.Import Notes:
Similarly to the save feature, you can also import an
.md
or.html
file from Dropbox , Google Drive, Gist or import content from your clipboard , and that can parse some HTML which might be usefulPermissions:
It is possible to change permissions to a note through the button on the share button on the top right of the menu, click the button and you will see the Sharing menu.
For read and write permissions, you can either choose: Owners, Signed-in users or Everyone.
For commenting permission, please click More in the sharing menu and choose either: Forbidden, Owners, Signed-in users or Everyone. You even can disable the commenting feature through the toggle to the right of the commenting label.
Only the owners of the note can change above permissions.
To invite specific user to a note, please read Invite Others to a Private Note.
Embed a Note:
Notes can be embedded using iframe as follows:
<iframe width="100%" height="500" src="https://hackmd.io/features" frameborder="0"></iframe>
Or you can use embed syntax to include a note seamlessly, please read Embedding another note.
Slide Mode:
You can use a special syntax to organize your note into slides.
After that, you can use the Slide Mode to make a presentation.
Visit the above link for details.
Book Mode:
You can make your notes into a book.
List your links in order or nest them.
Then use the Book Mode to make a collection.
Visit the above link for details.
View
Table of Contents:
You can look at the bottom right section of the view area, there is a ToC button .
Pressing that button will show you a current Table of Contents, and will highlight which section you’re at.
If the view area is wide enough, to ToC will show directly at the right section of the view area.
ToCs support up to three header levels.
Header link
Every header will automatically add a url link on the left side.
You can hover and click to anchor on it.
Edit:
Shortcut Keys:
Just like Sublime text, which is pretty quick and convenient.
Auto-Complete:
This editor provides full auto-complete hints in markdown.
:
to show hints.```
and plus a character to show hint. ```#
to show hint.[]
to show hint.{}
to show hint.!
to show hint.Title:
This will take the first level 1 header as the note title.
Tags:
Using tags as follows, the specified tags will show in your note list.
tags:
features
cool
updated
YAML Metadata
You can provide advanced note information to set the browser behavior (visit above link for details):
ToC:
Use the syntax
[TOC]
to embed table of content into your note.Emoji
You can type any emoji like this

ToDo List:
Code Block:
We support many programming languages, use the auto complete function to see the entire list.
Blockquote Tags:
Externals
YouTube
Vimeo
Gist
SlideShare
Speakerdeck
PDF
Caution: this might be blocked by your browser if not using an
https
URL.MathJax
You can render LaTeX mathematical expressions using MathJax, as on math.stackexchange.com, except the space after the start
$
and the space before the end$
are not allowed in the inline math:The Gamma function satisfying Γ(n)=(n−1)!∀n∈N is via the Euler integral
For block level math, please give
$
and a line break before and after your math formula:x=−b±√b2−4ac2a.
Γ(z)=∫∞0tz−1e−tdt.
UML Diagrams
Sequence Diagrams
You can render sequence diagrams like this:
Flow Charts
Flow charts can be specified like this:
Graphviz
Mermaid
Abc
Vega-Lite
Alert Area
Yes
This is a message
Watch out
Oh No!
Click to show details
You found me
Expand the spoiler container by default
You found me
Typography
Headers
Horizontal Rules
Typographic Replacements
Enable typographer option to see result.
© © ® ® ™ ™ § § ±
test… test… test… test?.. test!..
!!! ??? ,
Remarkable – awesome
“Smartypants, double quotes”
‘Smartypants, single quotes’
Emphasis
This is bold text
This is bold text
This is italic text
This is italic text
Deleted textlulala
Superscript: 19th
Subscript: H2O
Inserted text
Marked text
ruby base
Blockquotes
Lists
Unordered
+
,-
, or*
Ordered
1.
Start numbering with offset:
Code
Inline
code
Indented code
Block code “fences”
Syntax highlighting
Tables
Right aligned columns
Left aligned columns
Center aligned columns
Links
link text
link with title
Autoconverted link https://github.com/nodeca/pica
Images
Like links, Images also have a footnote style syntax
With a reference later in the document defining the URL location:
Show the image with given size
Footnotes
Footnote 1 link[1].
Footnote 2 link[2].
Inline footnote[3] definition.
Duplicated footnote reference[2:1].
Definition Lists
Definition 1
with lazy continuation.
Definition 2
Third paragraph of definition 2.
Compact style:
Abbreviations
This is an HTML abbreviation example.
It converts “HTML”, but keeps intact partial entries like “xxxHTMLyyy” and so on.
Footnote can have markup
and multiple paragraphs. ↩︎
Footnote text. ↩︎ ↩︎
Text of inline footnote ↩︎