Sidebar
Quick Definition
A sidebar is a widgetized area in your WordPress theme where you can add widgets like search bars, recent posts, or newsletter forms. Despite the name, sidebars can appear anywhere — not just on the side.
What Is a Sidebar?
In WordPress, a sidebar is technically defined as any widgetized area of your theme. According to the WordPress developer handbook, sidebars are areas where users can add widgets through the Customizer or the Widgets admin panel.
Despite the name, a sidebar doesn't have to be on the side of the page. Many themes use "sidebars" for footer widget areas, header widget areas, or any other section that accepts widgets. The name is a historical holdover from early WordPress themes where the widget area was literally a column on the left or right side of the content.
Common sidebar locations include:
- Right sidebar — the classic blog layout, a column next to the main content
- Left sidebar — less common, sometimes used on documentation sites
- Footer widget areas — often 3 or 4 columns at the bottom of every page
- Header widget area — above or below the navigation menu
Sidebars in Practice
In classic themes, sidebars are registered by the theme developer using the register_sidebar() function in functions.php. You manage them from Appearance → Widgets in your dashboard, where you drag and drop widgets into each sidebar area.
In block themes (WordPress 5.9+), traditional sidebars are replaced by template parts. Instead of a Widgets screen, you edit sidebar-like areas directly in the Site Editor using blocks. This gives you more design flexibility but works differently from the classic approach.
Typical widgets you'd find in a sidebar:
- Search bar
- Recent Posts or Popular Posts
- Categories or Tag Cloud
- Newsletter signup form
- Social media links
- About the author box
- Ad banners
Not every theme has a sidebar. Some modern themes use full-width layouts without any sidebar at all. If your theme supports sidebars, you'll see them listed under Appearance → Widgets.
Why It Matters
A well-designed sidebar keeps visitors engaged — it surfaces related content, encourages newsletter signups, and helps with navigation. But a cluttered sidebar with too many widgets slows your site and overwhelms readers. Stick to 3-5 essential widgets. For theme recommendations with good sidebar options, see our best themes guide and free themes roundup.