Common SEO Errors: an Audit of 270 Sites

We looked at what an SEO crawler finds most often on real sites. Of 270 sites in our sample, 81% (218 of 270) have at least one page with a title longer than 60 characters, and 73% (196 of 270) have images without width and height. Below is the ranking of common findings, how WordPress differs from other platforms, and a checklist of where to start.

Data: crawls 16 June to 8 November 2026, updated 8 November 2026

About the sample

The sites come from the PromoPilot SEO audit: 270 sites, the latest crawl of each, 23,084 HTML pages with a 200 response (median 98 pages per site). Of these, 74 sites run on WordPress (including WooCommerce) and 196 on other platforms. The sample is not random: these are sites their owners added to the audit or to a PromoPilot account, so we write "in our sample", not "on the internet". "Share of sites" means the site has at least one page with the finding; "share of pages" is pages with the finding out of all 23,084; "median on affected sites" is the share of pages with the finding within each such site.

The ranking: 12 common findings

Length rules need a caveat. Google trims a snippet by width in pixels, not by characters, so 60 characters for a title and 160 for a description are a rough guide. A long title is a signal that it may be cut off, not an error in itself.

What the findings mean

Snippets: title and description

The title and description are what a person sees in search results. Titles over 60 characters are on 81% of sites (218 of 270), descriptions over 160 on 68% (183 of 270). A missing description is a separate case: 32% of sites (87 of 270). Identical titles on different pages are on 28% of sites (76 of 270), and identical descriptions on 26% (70 of 270). Shortening and making them unique removes the risk of a trimmed or repeated snippet. We did not measure whether this changes rankings.

Images: size and alt text

An image without width and height makes the browser reserve no space, so the layout can jump while the page loads (this is what the CLS metric reflects). In our sample 73% of sites (196 of 270) have such images, and 51% of all pages (11,682 of 23,084). The missing alt text matters for accessibility and for image search: it is absent on 68% of sites (183 of 270). Both are cheap to fix in a template, and on the affected sites a median of 93% of pages lack image sizes and 87% lack alt, which suggests a template cause, not a one-off slip.

Structure: headings

No H1 is on 30% of sites (81 of 270), and on 33% (88 of 270) the H1 only repeats the title. Skipped heading levels (for example H2 straight to H4) appear on 29% (79 of 270). A clear heading outline helps both readers and crawlers understand what a page is about.

Thin pages and orphan pages

Pages with under 150 words are on 37% of sites (101 of 270), and orphan pages, which no crawled page links to, on the same 37% (101 of 270). These are different problems that often go together: a page with little text that nobody links to is hard to find and has little to show. Not every such page needs to stay; some are better merged or removed.

Structured data (schema.org)

No schema.org markup at all is on 34% of sites (91 of 270), and incomplete markup on 30% (81 of 270). Markup is not required for indexing; it helps search engines read the page type. If you add it, fill in the required fields.

WordPress against other platforms

WordPress sites more often have no meta description (64% of 74 against 20% of 196), a slow response (50% against 15%), no H1 (46% against 24%), long URLs (42% against 15%) and render-blocking scripts in the head (41% against 5%). In the other direction, schema.org markup is missing less often on WordPress (14% against 41%), which is most likely thanks to SEO plugins. We would not conclude that WordPress is bad: the differences come from themes and plugins, not from the platform core. The median site health score is the same: 61 for WordPress and 61.5 for the others.

Hreflang

Among the 136 sites that use hreflang, 24% (32 of 136) have no x-default, the entry that tells search engines which version to show to users whose language is not listed. And 11% (15 of 136) have a page that does not reference itself in its hreflang set, although each language version should list itself too.

What is rare

The crudest errors are uncommon: no title at all on 6% of sites (17 of 270), no viewport tag on 3% (8 of 270), redirect loops on 1% (4 of 270). Internal links to pages that return a 4xx error are more frequent, on 17% of sites (47 of 270). Crude errors are rare; template-level issues that can be fixed in one go are far more common.

Checklist: where to start

1. Make sure every page has a title and a meta description, and that they are not duplicated across pages.
2. Check titles over 60 and descriptions over 160 characters; keep the important words at the beginning.
3. Add width and height to images in the template.
4. Fill in alt for meaningful images.
5. Give every page one H1 that does not simply copy the title.
6. Find internal links that lead to 4xx pages and fix them.
7. Link orphan pages from relevant sections, or merge and remove the ones you do not need.
8. If the site has several languages, check x-default and self-reference in hreflang.

Check your own site

You can run the same kind of check on your site in the PromoPilot SEO audit. It shows these findings for your pages so you can decide what to fix first.

Methodology

• Source: the PromoPilot SEO audit (our own crawler). Sites that users added to the audit themselves or that were checked automatically when a project was added. The sample is not random: these are sites whose owners work on SEO, not the internet as a whole.
• Period: crawls completed 16 June to 8 November 2026. For each domain only the latest completed crawl with 10 or more pages is used. Test accounts and the PromoPilot site itself are excluded.
• Volume: 270 sites, 23,084 HTML pages with a 200 response (24,889 URLs in total). The crawl is limited by the plan's page limit: median 98 pages per site, so this is a slice of the home page and nearby sections, not the whole site.
• Unit: "share of sites" means the site has at least one page with the finding; "share of pages" is pages with the finding divided by all HTML pages with a 200 response.
• Median on affected sites: the share of pages with the finding within each site that has it; this is why 51% of all pages and a median of 93% do not contradict each other.
• Thresholds: title over 60 or under 10 characters; description over 160 or under 50; thin content under 150 words; server response over 3,000 ms; more than 150 outgoing links; URL over 115 characters; more than 2 blocking scripts in the head; keyword stuffing: one word over 6% of text on a page of 200 words or more; orphan page: no internal links to it from the crawled pages. Lengths in characters are approximate, since Google trims snippets by width in pixels: this is a signal that it may be cut, not an error.
• Hreflang: shares are counted out of the 136 sites that have hreflang on their pages.
• Platform: determined from signs in the page code (generator, paths, headers). WordPress means WordPress plus WooCommerce (74 sites); the other 196 sites include 123 where the platform could not be determined.
• Not in the ranking: checks added to the audit later and not present in every crawl (PageSpeed, Core Web Vitals, AI citation, llms.txt), and HSTS (covered in our 7 November study).
• Limitations: self-selected sites; the crawl stops at the page limit; we do not compare countries (too few sites per country); we did not measure the link between these findings and rankings. The findings are descriptive, not causal.

FAQ

What title length do I need?

There is no exact limit. Google trims a title by width in pixels, so about 60 characters is a rough guide. In our sample 81% of sites (218 of 270) have at least one title over 60 characters, and 32% of pages (7,465 of 23,084). Put the main words first and treat the number as a signal, not a rule.

Do images need width and height?

It is a good habit: the browser then reserves space and the page does not jump while loading. In our sample 73% of sites (196 of 270) have images without these attributes, and on the affected sites a median of 93% of pages has them, so it is usually fixed in one template.

What is an orphan page and how do I find it?

A page that no other page of the site links to. Crawlers and visitors find it hard to reach. In our sample 37% of sites (101 of 270) have at least one. To find them, compare the list of pages in your sitemap with the pages a crawler reaches by following links, or run an SEO audit.

Is schema.org markup required?

No, a page can be indexed without it. In our sample 34% of sites (91 of 270) have no markup and 30% (81 of 270) have incomplete markup. Markup helps search engines read the page type; add it where it fits the content, and check it is filled in completely.

How often should I check my site?

There is no single schedule. A reasonable habit is a check after every notable change to templates, plugins or structure, and a regular check on top of that. We did not measure how often problems return, so this is a practice, not a figure from the data.

How to cite

PromoPilot (2026). Common SEO Errors: an Audit of 270 Sites. Data 16 June to 8 November 2026. CC BY 4.0: https://promopilot.link/uploads/blog/research/seo-errors-0911/seo-errors-audit-2026-11-08.csv . Article: https://promopilot.link/en/blog/common-seo-errors-audit-270-sites

Download the data

The aggregate table (CSV, license CC BY 4.0): https://promopilot.link/uploads/blog/research/seo-errors-0911/seo-errors-audit-2026-11-08.csv. It contains aggregates only, with no domains.