# Group by Category

URL: /bengal/docs/0.5.1/theming/recipes/group-by-category/
Section: recipes
Tags: cookbook, filters, group_by

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Group by Category Display content organized by category, tag, or any frontmatter field. The Pattern {% let by_category = site.pages |> where('section', 'docs') |> group_by('category') %} {% for category, pages in by_category.items() |> sort %} <section> <h2>{{ category | title }}</h2> <ul> {% for page in pages |> sort_by('weight') %} <li><a href="{{ page.href }}">{{ page.title }}</a></li> {% end %} </ul> </section> {% end %} What's Happening Step Purpose group_by('category') Creates a dict: {category: [pages]} .items() Iterate key-value pairs | sort Alphabetize categories sort_by('weight') Order pages within each category Variations By Year By Tag (Taxonomy) Nested Groups {# Group blog posts by publication year #} {% let posts = site.pages |> where('section', 'blog') |> sort_by('date', reverse=true) %} {% let current_year = none %} {% for post in posts %} {% let post_year = post.date.year %} {% if post_year != current_year %} {% let current_year = post_year %} <h2>{{ post_year }}</h2> {% end %} <li><a href="{{ post.href }}">{{ post.title }}</a></li> {% end %} {# Show all tags with their post counts #} {% for tag, data in site.taxonomies.tags.items() |> sort %} <div class="tag"> <a href="{{ data.href }}">{{ tag }}</a> <span class="count">{{ data.pages | length }}</span> </div> {% end %} {# Group by category, then by author #} {% let by_category = site.pages |> group_by('category') %} {% for category, cat_pages in by_category.items() %} <h2>{{ category }}</h2> {% let by_author = cat_pages |> group_by('author') %} {% for author, author_pages in by_author.items() %} <h3>{{ author }}</h3> {% for page in author_pages %} <li>{{ page.title }}</li> {% end %} {% end %} {% end %} Handle Missing Values Pages without the grouped field go into a None group: {% let by_category = pages |> group_by('category') %} {% for category, pages in by_category.items() %} {% if category %} <h2>{{ category }}</h2> {% else %} <h2>Uncategorized</h2> {% end %} {# ... #} {% end %} Info Seealso Template Functions — All filter options Filter by Tags — Multi-criteria filtering

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Metadata:
- Author: lbliii
- Word Count: 321
- Reading Time: 2 minutes