Customize the look of your WordPress.org site’s blog page by changing full blog posts to excerpts on your WordPress site’s front page. Here are four ways to shorten your posts:
1) Theme settings
Depending on your theme, you may have the option to shorten your full-length posts down to post excerpts within your theme’s settings, which would be under the “Appearance” tab.
2) Theme editor
You can hard-wire your WordPress theme to automatically display just the posts’ excerpts; you can switch out some code in your theme’s editor if the above doesn’t work, and you don’t like the options below.
You can swap out code in your index.php, archive.php, and category.php files within your editor. Make sure to save the original code in notepad or such before you make any changes, or better yet, create a child theme for these and any other changes you’ll make to your blog’s theme.
This information is from wpbeginner.com.
3) Use the Excerpt field
Your custom post summary will also show up just by typing one in the Excerpt box below any blog post. Here you can also add some HTML code if you’d like.
However, WordPress does not automatically provide a link to the full post with this option. To have “read more” button after the excerpt, you must use some code in the excerpt box, after your text about the post.
This information is from codex.wordpress.org.
4) Post code addition
Another option for shortening blog posts’ lengths on the front page of your WordPress site is to use the “more” html tag. This technically isn’t an excerpt, but rather the first few words in your post–a “teaser” of sorts.
By using this tag, you’re able to customize where you’d like the break in the article, between what shows up on the main blog page’s list of articles and what visitors can read once they click on the “more” link.
While typing out a blog post, simply place your cursor where you’d like the break. In the visual editor, locate and click on the symbol showing two pages separated by a dotted line: (if you can’t find it, use the html text editor side to add it, or read about installing the Tiny MCE Editor that makes this button available). If you’re in the html editor, find the “more” button like it shows below (this will add <!–more–> coding).This tag will only show a “more” link for viewers to click on when they’re browsing from the front blog page. It won’t be visible when they click on that post to read it.
About custom excerpts
With all the above, the “excerpt” will be the first few words/sentences of your blog post automatically. However, you can write a custom excerpt with the first three options; this custom text will then show instead of the first bit of your actual blog post. In this way, you can create a brief summary or description of your post.
With excerpts, you can have the RSS feed display that summary instead of the full blog post. Select the option to display them instead by going to your Settings tab in your Dashboard, then going to the Reading option.
You can also use them in other areas of your WordPress site when you’d prefer a more concise option to full blog posts, like in search results and archives. Read up on excerpts more in WordPress.org’s codex.
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