Categories

How to set categories on a post

You can use either category or categories. Both get evaluated by Jekyll as a category and made available on page.categories.

Set category field

Using category only accepts a single value.

  • _posts/2021-01-02-abc.md 
      ---
  category: foo
  ---

Set categories field

Using categories lets you use specifiy multiple values.

Either by using spaces between words in a string - this is normally just a single string in YAML but Jekyll does magic to convert to a array.

  • _posts/2021-01-02-abc.md 
      ---
  categories: foo bar bazz-buzz
  ---

Or using an array.

  • _posts/2021-01-02-abc.md 
      ---
  categories:
    - foo
    - bar
    - bazz-buzz
  ---

The resulting path will be:

  • foo/bar/bazz-buzz/2021/01/02/abc.html

Do not use quotes.

Use a dash for multi-word categories - e.g. bazz-buzz. If you used space in the array form above, then your output path has a space in, which is not good - rather use a dash.

Put posts directory in a directory

Here using a directory foo which contains _posts directory.

  • foo/_posts/2021-01-02-abc.md 
      ---
  ---

Resulting categories:

["foo"]

Resulting path:

  • foo/bar/2021/01/02/abc.html

Here using an outer directory category and the frontmatter categories together.

  • foo/_posts/2021-01-02-abc.md 
      ---
  categories: bar
  ---

Resulting categories:

["foo", "bar"]

Put a directory inside the posts directory

You could even a directory inside of _posts.

But this would only be for your own structure convenience. Using _posts/foo below does not affect the categories variable or the output path.

  • _posts/foo/2021-01-02-abc.md 
      categories: bar

Resulting categories:

["bar"]

Output path:

  • bar/2021/01/02/abc.html

Note the foo directory is absent from both.