A block that supports alignment has three widths in its toolbar:
| Alignment | Width |
|---|---|
| (none) | The content column — 620px on a narrow layout |
| Wide width | 900px |
| Full width | Edge to edge |
The control is the leftmost button in the block toolbar, on Image, Cover, Gallery, Group, Columns, Table, Media & Text, Query Loop and a few others.
Use them instead of changing the layout
A narrow post can already break out. One big photograph in the middle of an article does not need the Full width layout — it needs one block set to Wide.
Reach for the full-width layout when the whole entry is wide; reach for these when one block is.
What happens in each layout
| Layout | Wide | Full |
|---|---|---|
| Narrow | Grows to 900px, centred | Edge to edge |
| Full width | Already at container width; little visible change | Edge to edge |
| Sidebar left / right | Constrained by the content column | Constrained by the content column |
That last row is the one that catches people out: a sidebar layout has no edge to run to. The content column is a column, and a block cannot escape it without running under the sidebar. Wide and Full still work, but they max out at the column width. If you want genuinely edge-to-edge blocks, the entry needs a layout with no sidebar.
In the editor
The canvas is 620px wide and 900px for wide blocks, matching the front end — see theme.json.
Set the post or page to Full width in the Post options / Page options box and the canvas widens immediately, so you are composing at the width the entry will actually render at. On the Full width layout the editor keeps a gutter at each side rather than running blocks to the very edge, which is what the front end does too.
Using them well
- One full-width image in a long article is dramatic. Four is a slideshow.
- Full-width Cover blocks are the standard way to open a landing page. Pair with Hide page title — see Full width and narrow.
- Wide is the underused one. It gives a photograph or a table more room without breaking the page’s frame, and it usually looks better than Full inside an article.
- A wide table beats a full-width one: a table that runs to the browser edge has no margin for the eye to rest against.