#### MarsEdit Help | Solutions By Topic | Q&A

# Applying Preview Text Filters

Text Filters are used to transform your blog post’s content before displaying it in the preview window. This can be useful when simulating the behavior of your blog system, so that your preview looks identical to the final, published format.

Important: Text Filters do not alter the content of your blog post before sending it to the server. They are used only to preview what your post will look like after similar text processing is performed on the blog server.

MarsEdit includes built-in support for Markdown and Convert Line Breaks filters. You may apply a filter to an individual post, or you may set a filter as a default for all future posts for a blog.

To set a text filter as the default for a blog, open the settings dialog for the blog, and select the Preview Text Filter in the Editing tab.

Text Filters are stored in MarsEdit’s data folder, within the `TextFilters/` folder. To add a custom text filter to MarsEdit, just copy it into this folder.

If your web server doesn't support text filters, you can still use MarsEdit convert your writing, say from Markdown to HTML. Just edit your post in "Plain Text Mode" in MarsEdit, and turn on the option the blog's Publishing settings to "Apply Preview Filter to Content" before publishing.