Show a post's word count in Jekyll

Jekyll can count the words in a post without a plugin. Pass the post content through Liquid’s number_of_words filter:

{% assign word_count = post.content | number_of_words %}
<p>{{ word_count }} words</p>

Use page.content instead of post.content when the snippet is part of a single-post layout. The correct variable depends on where the code runs, but the filter stays the same.