Want to instantly preview finnicky markdown files, but don't want to leave your favorite editor, or have to do it in some crappy browser textarea? vim-instant-markdown is your friend! When you open a markdown file in vim, a browser window will open which shows the compiled markdown in real-time, and closes once you close the file in vim.

As a bonus, github-flavored-markdown is supported, and styles used while previewing are the same as those github uses!

You first need to have node.js with npm installed. Then:

• [sudo] npm -g install instant-markdown-d
• If you're on Linux, ensure the following packages are installed:
  • xdg-utils
  • curl
  • nodejs-legacy (for Debian-based systems)
• If you're on Windows, you will need into install cURL and put it on your %PATH%.
• Copy the after/ftplugin/markdown/instant-markdown.vim file from this repo into your ~/.vim/after/ftplugin/markdown/ (creating directories as necessary), or follow your vim package manager's instructions.
• Ensure you have the line filetype plugin on in your .vimrc
• Open a markdown file in vim and enjoy!

By default, vim-instant-markdown will update the display in realtime. If that taxes your system too much, you can specify

let g:instant_markdown_slow = 1

before loading the plugin (for example place that in your ~/.vimrc). This will cause vim-instant-markdown to only refresh on the following events:

• No keys have been pressed for a while
• A while after you leave insert mode
• You save the file being edited

By default, vim-instant-markdown will automatically launch the preview window when you open a markdown file. If you want to manually control this behavior, you can specify

let g:instant_markdown_autostart = 0

in your .vimrc. You can then manually trigger preview via the command :InstantMarkdownPreview. This command is only available inside markdown buffers and when the autostart option is turned off.

By default, the server only listens on localhost. To make the server available to others in your network, edit your .vimrc and add

let g:instant_markdown_open_to_the_world = 1

Only use this setting on trusted networks!

By default, scripts are blocked. To allow scripts to run, edit your .vimrc and add

let g:instant_markdown_allow_unsafe_content = 1

By default, external resources such as images, stylesheets, frames and plugins are allowed. To block such content, edit your .vimrc and add

let g:instant_markdown_allow_external_content = 0

OSX, Unix/Linuxes*, and Windows**.

_{*: One annoyance in Linux is that there's no way to reliably open a browser page in the background, so you'll likely have to manually refocus your vim session everytime you open a Markdown file. If you have ideas on how to address this I'd love to know!}

_{**: In Windows, there's no easy way to execute commands asynchronously without popping up a cmd.exe window. Thus, if you run this plugin without g:instant_markdown_slow, you might experience performance issues.}

It's not working!

• Make sure instant-markdown-d was installed as a global module (e.g. using npm -g install)
• If you're on OSX and are using zsh, try to add set shell=bash\ -i in your .vimrc to set interactive bash as the default vim shell. (See this issue)

Why don't my <bla>.md files trigger this plugin?

By default, vim versions before 7.4.480 only recognize files ending with .markdown, .mdown, and README.md as markdown files. If you want <anything>.md to be recognized, I recommend installing one of many markdown plugins available, such as this one.

If you're curious, the code for the mini-server component for this plugin can be found at http://github.com/suan/instant-markdown-d. A plugin can easily be written for any editor to interface with the server to get the same functionality found here.