WordPress SEO plugins: what Yoast and Rank Math do, and what's left to you

The mistake I see most often in WordPress SEO is relying on a plugin without knowing what it does or how to use it. Someone installs Yoast SEO or Rank Math, works on the dots until they turn green, and considers the job done. Meanwhile the site doesn’t show up for the searches that bring in customers, and nobody can explain why, because “the plugin says everything is fine”.

This article covers what these plugins do, what Google says about it and what’s worth configuring. The sources are the official docs from Google, WordPress, Yoast and Rank Math, checked on 29 October 2026.

In short

• An SEO plugin writes the title, meta description, indexing directives and structured data into your pages, and generates a sitemap.
• The keyword you type into the plugin never reaches Google. The plugin uses it to analyse your text.
• Scores and traffic lights follow rules chosen by the plugin’s authors, and on some points Google says the opposite.
• Google ignores the meta keywords tag and decides for itself which title and description to show.
• Picking the searches to target and writing pages that answer them is still manual work.

What an SEO plugin does

Yoast SEO and Rank Math cover the same basics. For each page they let you set the <title> and meta description, with templates for posts, products and categories, and ask search engines not to index certain pages (noindex). They generate their own XML sitemap, separate from the one WordPress has produced at /wp-sitemap.xml since version 5.5 (WordPress 5.5); Rank Math, for example, publishes it at /sitemap_index.xml (Rank Math). They add structured data: Yoast marks up pages as WebPage and posts as Article automatically, and uses its Site representation settings to say whether an organisation or a person is behind the site (Yoast).

Then there’s the panel under the editor, where you enter a keyword and get a score and a list of coloured checks. People spend the most time there, and it matters the least.

Titles and descriptions: you suggest, Google decides

The title you write in the plugin is one of the sources Google uses for the title link in results, together with the visible title on the page, <h1> headings, the og:title tag and the anchor text of links pointing to the page (Google). Snippets come mainly from the page content. Google uses the meta description when it describes the page more accurately, and may show different snippets for different searches (Google).

The coloured length bars are the plugin’s estimate: Google sets no length limit and truncates text to fit the device width (Google). It matters more that every page has its own title, with no boilerplate repeated across the site and a short version of the site name.

A sitemap helps Google find your pages

A sitemap helps search engines discover your URLs. Google says it doesn’t guarantee that listed pages get crawled and indexed, and that a site of about 500 pages or fewer with good internal linking may not need one (Google). Having one does no harm; what you need to check is what’s in it.

Structured data: the plugin doesn’t know what you sell

Google uses structured data for rich results, but doesn’t guarantee to show them even when the markup is correct. The data also has to match what visitors can see on the page (Google).

The rules change, too, and the plugin won’t tell you. How-to rich results stopped appearing in 2023. FAQ rich results, the expandable questions under a search result, have not been shown in Google Search since 7 May 2026 (Google, documentation updates). The plugins’ FAQ blocks can still help readers, but the questions no longer appear under your result.

The green score measures the plugin’s own rules

The main keyword (focus keyphrase in Yoast, focus keyword in Rank Math) isn’t passed to search engines. Both say so: Yoast describes it as not a signal it gives to search engines (Yoast), and Rank Math says it is only used to analyse your content (Rank Math).

The score depends on rules the plugin’s authors chose, and some don’t match what Google says. Two examples from Rank Math’s guide to its own tests (Rank Math):

• the content length test only gives full marks above 2,500 words. Google says it has no preferred word count (Google) and that length alone doesn’t matter for ranking (Google);
• a keyword in the URL is described as a ranking signal. Google says keywords in the domain name or URL path alone have hardly any effect beyond appearing in breadcrumbs (Google).

The plugins hedge this themselves. Yoast says an article can rank without passing every readability check (Yoast). Rank Math says a post with a lower score can still rank well (Rank Math) and that the plugin’s effectiveness depends on how well you use it (Rank Math). And in June 2026 Google wrote that third-party SEO tools have no access to its internal ranking data and can’t guarantee results (Google).

What’s left to you

The searches to target and the content that answers them still have to be chosen and written. The plugin can tell you whether “commercial solar panel installation” appears in your first paragraph. It can’t tell you whether that’s what your customers type, or whether your page answers better than the ones Google already shows.

For the first question, start with Search Console. The Performance report lists the queries your site already appears for, with impressions and clicks (Search Console). Compare them with the keywords you entered in the plugin.

For the second, read the results Google shows for that search and work out what the person searching wants: a price, a comparison, an address, instructions. Google asks for content written for people, and lists writing to a target word count among its warning signs (Google).

That’s where I start, and only then do I configure the plugin to do its part. For a plant nursery with an online shop I did the SEO analysis and the work on the site; rankings improved and online sales went up 35%.

Checklist: what to configure

1. Search engine visibility. Under Settings > Reading, the box asking search engines not to index the site must be unticked on the live site; when it’s ticked, WordPress adds noindex, nofollow to every page (WordPress). Check it again whenever a site moves from staging to production.
2. A single active SEO plugin. Two plugins writing titles, descriptions and structured data produce duplicate tags. Themes that add their own structured data can cause the same problem (Yoast).
3. Title templates with a short site name at the end and no phrase repeated on every page (Google).
4. Hand-written titles and descriptions for the home page, categories and main services or products. Templates are fine for the rest.
5. Site representation: organisation or person, name, logo, official social profiles.
6. Pages to exclude. For example, author archives on a single-author site, which Rank Math suggests disabling or noindexing because they duplicate your posts (Rank Math).
7. Sitemap. Open it in a browser, check the right pages are there and the excluded ones aren’t, then submit it in Search Console.
8. Search Console connected, because its data comes straight from Google (Google).
9. A check after every theme or plugin change, with the Rich Results Test and the URL Inspection tool (Google).

What to ignore

• The meta keywords tag. Google doesn’t use it for indexing or ranking (Google). Yoast removed the field in version 6.3 (Yoast); Rank Math leaves it out by default (Rank Math).
• A 100/100 score and all-green lights, along with minimum word counts.
• Keyword density. Repeating the same words unnaturally is keyword stuffing, which goes against Google’s spam policies (Google).
• The number and order of headings, which don’t matter for Google Search (Google). A logical order does help screen reader users, so keep it for accessibility.
• FAQ and How-to blocks added for rich results, which Google no longer shows.

If you want to know what the plugin is doing on your site and which searches are worth targeting, the WordPress and SEO consulting page explains how I work.