Web Almanac Data Reveals CMS Plugins Are Setting Technical SEO Standards

If greater than half the net runs on a content material administration system, then the vast majority of technical Search engine marketing requirements are being positively formed earlier than an Search engine marketing even begins work on it. That’s the lens I took into the 2025 Web Almanac SEO chapter (for readability, I co-authored the 2025 Internet Almanac Search engine marketing chapter referenced on this article).

Somewhat than asking how particular person optimization choices affect efficiency, I needed to know one thing extra elementary: How a lot of the net’s technical Search engine marketing baseline is set by CMS defaults and the ecosystems round them.

Search engine marketing usually feels intensely hands-on – maybe an excessive amount of so. We debate canonical logic, structured information implementation, crawl management, and metadata configuration as if every website had been a bespoke engineering venture. However when 50%+ of pages within the HTTP Archive dataset sit on CMS platforms, these platforms turn into the invisible standard-setters. Their defaults, constraints, and have rollouts quietly outline what “regular” appears to be like like at scale.

This piece explores that affect utilizing 2025 Web Almanac and HTTP Archive data, particularly:

• How CMS adoption developments observe with core technical Search engine marketing indicators.
• The place plugin ecosystems seem to form implementation patterns.
• And the way rising requirements like llms.txt are spreading consequently.

The query is just not whether or not SEOs matter. It’s whether or not we’ve been underestimating who units the baseline for the trendy internet.

The Spine Of Internet Design

The 2025 CMS chapter of the Internet Almanac noticed a milestone hit with CMS adoption; over 50% of pages are on CMSs. In case you had been unsold on how a lot of the net is carried by CMSs, over 50% of 16 million websites is a major quantity.

With regard to which CMSs are the most well-liked, this once more might not be shocking, however it’s price reflecting on with regard to which has the most impact.

WordPress is still the most used CMS, by a great distance, even when it has dropped marginally within the 2024 information. Shopify, Wix, Squarespace, and Joomla path a great distance behind, however they nonetheless have a major affect, particularly Shopify, on ecommerce particularly.

Search engine marketing Features That Ship As Defaults In CMS Platforms

CMS platform defaults are vital, this – I consider – is that a whole lot of primary technical Search engine marketing requirements are both default setups or for the comparatively small variety of web sites which have devoted SEOs or individuals who at the least construct to/work with Search engine marketing greatest apply.

Once we discuss “greatest apply,” we’re on barely shaky floor for some, as there isn’t a common, prescriptive view on this one, however I might take into account:

• Descriptive “Search engine marketing-friendly” URLs.
• Editable title and meta description.
• XML sitemaps.
• Canonical tags.
• Meta robots directive altering.
• Structured information – at the least a primary degree.
• Robots.txt enhancing.

Of the primary CMS platforms, here’s what they – self-reportedly – have as “default.” Be aware: For some platforms – like Shopify – they’d say they’re Search engine marketing-friendly (and to be sincere, it’s “ok”), however many SEOs would argue that they’re not pleasant sufficient to go this take a look at. I’m not weighing into these nuances, however I’d say each Shopify and people SEOs make some good factors.

Based mostly on the above, I might say that almost all Search engine marketing fundamentals will be lined by most CMSs “out of the field.” Whether or not they work effectively for you, otherwise you can’t obtain the actual configuration that your particular circumstances require, are two different vital questions – ones which I’m not taking over. Nonetheless, it usually comes down to those factors:

1. It’s potential for these platforms for use badly.
2. It’s potential that the enterprise logic you want will break/not work with the above.
3. There are many extra superior Search engine marketing options that aren’t out of the field, which can be simply as vital.

We’re speaking about foundations right here, however after I mirror on what shipped as “default” 15+ years in the past, progress has been made.

Fingerprints Of Defaults In The HTTP Archive Information

On condition that a whole lot of CMSs ship with these requirements, do these Search engine marketing defaults correlate with CMS adoption? In some ways, sure. Let’s discover this within the HTTP Archive information.

Canonical Tag Adoption Correlates With CMS

Combining canonical tag adoption information with (all) CMS adoption over the past 4 years, we will see that for each cell and desktop, the developments appear to comply with one another fairly carefully.

Working a easy Pearson correlation over these parts, we will see this robust correlation even clearer, with canonical tag implementation and the presence of self-canonical URLs.

What differs is the cell correlation of canonicalized URLs; that appears to be a adverse correlation on cell and a decrease (however nonetheless constructive) correlation on desktop. A drop in canonicalized pages is basically inflicting this adverse correlation, and the explanations behind this may very well be many (and tougher to make sure of).

Canonical tags are an important factor for technical Search engine marketing; their continued adoption does actually appear to trace the expansion in CMS use, too.

Schema.org Information Sorts Correlate With CMS

Schema.org sorts in opposition to CMS adoption present comparable developments, however are much less definitive total. There are a lot of several types of Schema.org, but when we plot CMS adoption in opposition to those most typical to Search engine marketing issues, we will observe a broadly rising image.

Excluding Schema.org WebSite, we will see CMS development and structured information following comparable developments.

However we should be aware that Schema.org adoption is sort of significantly decrease than CMSs total. This may very well be on account of most CMS defaults being far much less complete with Schema.org. Once we take a look at particular CMS examples (shortly), we’ll see far-stronger hyperlinks.

Schema.org implementation remains to be largely intentional, specialist, and never as widespread because it may very well be. If I had been a search engine or creating an AI Search software, would I depend on common adoption of those, seeing the information like this? Presumably not.

Robots.txt

On condition that robots.txt is a single file that has some agreed requirements behind it, its implementation is way less complicated, so we might anticipate increased ranges of adoption than Schema.org.

The presence of a robots.txt is fairly vital, largely to restrict crawl of engines like google to particular areas of the positioning. We’re beginning to see an evolution – we famous within the 2025 Internet Almanac Search engine marketing chapter – that the robots.txt is used much more as a governance piece, quite than simply housekeeping. A key signal that we’re utilizing our key instruments in another way within the AI search world.

However earlier than we take into account the extra superior implementations, how a lot of a component does a CMS have in making certain a robots.txt is current? Seems like over the past 4 years, CMS platforms are driving a major quantity extra of robots.txt information serving a 200 response:

What’s extra curious, nevertheless, is when you think about the file of the robots.txt information. Non-CMS platforms have robots.txt information which can be considerably bigger.

Why might this be? Are they extra superior in non-CMS platforms, longer information, extra bespoke guidelines? Likely in some instances, however we’re lacking one other affect of a CMSs requirements – compliant (legitimate) robots.txt information.

A whole lot of robots.txt information serve a sound 200 response, however usually they’re not txt information, or they’re redirecting to 404 pages or comparable. Once we restrict this record to solely information that include user-agent declarations (as a proxy), we see a special story.

Approaching 14% of robots.txt information served on non-CMS platforms are probably not even robots.txt information.

A robots.txt is straightforward to arrange, however it’s a aware determination. If it’s forgotten/neglected, it merely gained’t exist. A CMS makes it extra prone to have a robots.txt, and what’s extra, when it’s in place, it makes it simpler to handle/preserve – which IS key.

WordPress Particular Defaults

CMS platforms, it appears, cowl the fundamentals, however extra superior choices – which nonetheless must be defaults – usually want extra Search engine marketing instruments to allow.

Interrogating WordPress-specific websites with the HTTP Archive information can be best as we get the biggest pattern, and the Wapalizer information provides a dependable strategy to decide the affect of WordPress-specific Search engine marketing instruments.

From the Internet Almanac, we will see which Search engine marketing instruments are essentially the most put in on WordPress websites.

For anybody working inside Search engine marketing, that is unlikely to be shocking. If you’re an Search engine marketing and labored on WordPress, there’s a excessive likelihood you’ve got used both of the highest three. What IS price contemplating proper now’s that whereas Yoast Search engine marketing is by far essentially the most prevalent inside the information, it’s seen on barely over 15% of web sites. Even the most well-liked Search engine marketing plugin on the most well-liked CMS remains to be a comparatively small share.

Of those prime three plugins, let’s first take into account what the variations of their “defaults” are. These are just like a few of WordPress’s, however we will see many extra superior options that come as normal.

Editable metadata, structured information, robots.txt, sitemaps, and, extra lately, llms.txt are essentially the most notable. It’s price noting that a whole lot of the performance is extra “back-end,” so not one thing we’d be as simply in a position to see within the HTTP Archive information.

Structured Information Influence From Search engine marketing Plugins

We will see (above) that structured information implementation and CMS adoption do correlate; what’s extra attention-grabbing right here is to know the place the important thing drivers themselves are.

Viewing the HTTP Archive information with a easy section (Search engine marketing plugins vs. no Search engine marketing plugins), from the newest scoring paints a stark image.

Once we restrict the Schema.org @sorts to essentially the most related to Search engine marketing, it’s actually clear that some structured information sorts are pushed actually laborious utilizing SEO plugins. They don’t seem to be fully absent. Folks could also be utilizing lesser-known plugins or coding their very own options, however ease of implementation is implicit within the information.

Robots Meta Help

One other discovering from the Search engine marketing Internet Almanac 2025 chapter was that “comply with” and “index” directives had been essentially the most prevalent, although they’re technically redundant, as having no meta robots directives is implicitly the identical factor.

Inside the chapter quantity crunching itself, I didn’t dig in a lot deeper, however figuring out that every one main Search engine marketing WordPress plugins have “index,comply with” as default, I used to be wanting to see if I might make a stronger connection within the information.

The place Search engine marketing plugins had been current on WordPress, “index, comply with” was set on over 75% of root pages vs. <5% of WordPress websites with out Search engine marketing plugins.

Given the ubiquity of WordPress and Search engine marketing plugins, that is probably an enormous contributor to this explicit configuration. Whereas that is redundant, it isn’t flawed, however it’s – once more – a key instance of whether or not a number of of the primary plugins set up a de facto normal like this, it actually shapes a good portion of the net.

Diving Into LLMs.txt

One other key space of change from the 2025 Internet Almanac was the introduction of the llms.txt file. Not an express endorsement of the file, however quite a tacit acknowledgment that this is a crucial information level within the AI Search age.

From the 2025 information, simply over 2% of web sites had a sound llms.txt file and:

• 39.6% of llms.txt information are associated to All-in-One Search engine marketing.
• 3.6% of llms.txt information are associated to Yoast Search engine marketing.

This isn’t essentially an intentional act by all these concerned, particularly as Rank Math allows this by default (not an opt-in like Yoast and All-in-One Search engine marketing).

For the reason that first information was gathered on July 25, 2025 if we take a month-by-month view of the information, we will see additional development since. It’s laborious to not see this as rising confidence on this markup OR at the least, that it’s really easy to allow, extra persons are probably hedging their bets.

Conclusion

The Internet Almanac information means that Search engine marketing, at a macro degree, strikes much less due to particular person SEOs and extra as a result of WordPress, Shopify, Wix, or a serious plugin ships a default.

• Canonical tags correlate with CMS development.
• Robots.txt validity improves with CMS governance.
• Redundant “index,comply with” directives proliferate as a result of plugins make them express.
• Even llms.txt is already spreading via plugin toggles earlier than it even will get full consensus.

This doesn’t diminish the affect of Search engine marketing; it reframes it. Particular person practitioners nonetheless create aggressive benefit, particularly in superior configuration, structure, content material high quality, and enterprise logic. However the baseline state of the net, the technical ground on which every part else is constructed, is more and more set by product groups delivery defaults to thousands and thousands of web sites.

Maybe we must always take into account that if CMSs are the infrastructure layer of recent Search engine marketing, then plugin creators are de facto requirements setters. They deploy “greatest apply” earlier than it turns into doctrine

That is the way it ought to work, however I’m additionally not totally comfy with this. They normalize implementation and even create new conventions just by making them zero-cost. Requirements which can be redundant have the power to endure as a result of they’ll.

So the query is much less about whether or not CMS platforms affect Search engine marketing. They clearly do. The extra attention-grabbing query is whether or not we, as SEOs, are paying sufficient consideration to the place these defaults originate, how they evolve, and the way a lot of the net’s “greatest apply” is basically simply the trail of least resistance shipped at scale.

An Search engine marketing’s worth shouldn’t be interpreted via the quantity of hours they spend discussing canonical tags, meta robots, and guidelines of sitemap inclusion. This ought to be normal and default. If you wish to have an out-sized affect on Search engine marketing, foyer an current software, create your individual plugin, or drive curiosity to affect change in a single.

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