SEO over-optimisation is applying optimisation techniques beyond the point where they help: the page keeps being written for the algorithm and stops working for the person reading it.
The word does not appear in Google's documentation. There are twenty named spam policies and sixteen types of manual action. Whatever falls outside those lists does not lead to penalties: it leads to pages that Google rewrites, shortens or shows lower down without telling you.
We measured the most visible effect on the UK SERP. Of the nine organic results on page one for "seo agency london", Google showed a title different from the one written in the code in six cases.
In Google's documentation, "over-optimisation" does not exist
Google Search's spam policies list twenty categories, each with its own name: cloaking, doorway abuse, expired domain abuse, hacked content, hidden text and link abuse, keyword stuffing, link spam, machine-generated traffic, malicious practices, misleading functionality, scaled content abuse, scraping, site reputation abuse, sneaky redirects, thin affiliation, user-generated spam, scams and fraud, policy circumvention, and the two entries on legal and personal information removals. "Over-optimization" is not there, in any form.
Two definitions are worth reading in full, because they are narrower than the way they are usually retold. Keyword stuffing is "filling a web page with keywords or numbers in an attempt to manipulate rankings in Google Search results". Link spam is "creating links to or from a site primarily for the purpose of manipulating search rankings". Both include a condition of intent: manipulation. A clumsy page is not a page that manipulates.
On the other side is the Manual Actions report in Search Console, which lists sixteen types of action. Three of them concern excessive optimisation: "Hidden text and/or keyword stuffing", "Unnatural links to your site" and "Thin content with little or no added value". If that report shows a green tick, no reviewer has touched your site, and the drop you are looking at has another cause. The step-by-step check is in the guide to Google penalties.
The term comes from something said in 2012
March 2012, an SXSW panel called "Dear Google & Bing: Help Me Rank Better!". Matt Cutts, then head of Google's webspam team, says they are working on a change aimed at people who do "over optimization", to level the playing field between those who overdo SEO and those who simply write good content. Barry Schwartz reported it on Search Engine Land.
The following month came the webspam update that everyone would call Penguin. Google wrote on its blog that it affected "about 3.1% of queries in English to a degree that a regular user might notice", and that it targeted sites using techniques designed to "look for shortcuts or loopholes that would rank pages higher than they deserve to be ranked".
From then on "over-optimisation" stayed in the industry's vocabulary and disappeared from Google's. Much of what ranks for the term today still recites the list of prohibitions from those years, often with a "safe" keyword density percentage that no Google document has ever given.
Google rewrites exactly what you optimised
The blue headline in the SERP is not your title tag: it is the "title link", and Google says it builds it from seven different sources. The title element, the main visual title on the page, heading elements such as the H1, the og:title tag, other large and prominent text, anchor text on the page and the anchor text of links pointing to the page. The documentation also says when it steps in: "If we've detected an issue on the page, we may try to generate an improved title link from anchors, on-page text, or other sources". The first two problems listed are keyword stuffing, with the example "Foobar, foo bar, foobars, foo bars", and boilerplate titles that change by a single detail.
Cyrus Shepard put a number on how often it happens in a Zyppy study of 80,959 titles collected from 2,370 sites in the first quarter of 2022. Google had changed 61.6% of them. Titles over 70 characters were rewritten 99.9% of the time, those between 51 and 60 characters 39-42% of the time, the least touched band of all.
We wanted to see it on a live commercial query, so we checked. On 26 September 2026 we took the organic results on page one for "seo agency london" on Google UK, desktop, located in London (the query opens with a local pack; the organic results start below it), and compared the title shown in the SERP with each page's actual title tag, read directly from the code.
| Pos. | Domain | Title in the code (characters) | Title shown by Google | Change |
|---|---|---|---|---|
| 1 | rapidseo.london | SEO Services London - SEO Agency London - SEO in London - Rapid SEO London (74) | Rapid SEO London: SEO Services London - SEO Agency ... | brand moved to the front, truncated |
| 2 | found.co.uk | SEO Agency London | Win at Search with SEO Agency UK | Found (60) | Win at Search with SEO Agency UK | Found | keyword prefix removed |
| 3 | goup.co.uk | SEO Agency London | London's Leading SEO Services (49) | identical to the title tag | none |
| 4 | clutch.co | Top SEO Agencies in London - Sep 2026 Rankings | Clutch.co (58) | Top SEO Agencies in London - Sep 2026 Rankings | brand removed |
| 5 | clickslice.co.uk | A Bespoke SEO Agency In London | Trusted SEO Company UK (55) | identical to the title tag | none |
| 6 | seoworks.co.uk | SEO Services London - The Best SEO Company in London (52) | identical to the title tag | none |
| 7 | agencies.semrush.com | Best SEO Companies in London 2026 | Semrush (43) | Best SEO Companies in London 2026 | brand removed |
| 8 | ink-digital.co.uk | London SEO Agency & Services | Ink Digital (42) | London SEO Agency & Services | brand removed |
| 9 | firstplaceseo.co.uk | SEO Company London | SEO Services & AI Search Optimisation | First Place SEO (76) | First Place SEO: SEO Company London | SEO Services & AI ... | brand moved to the front, truncated |
Six titles out of nine changed. The clearest case is rapidseo.london: the most loaded title in the group, with "SEO" four times and "London" four times in 74 characters, is the one Google reshuffled most, pulling the brand to the front and cutting off the rest. Found's title opened with the exact query and Google dropped exactly that part. The three pages left intact, goup.co.uk, clickslice.co.uk and seoworks.co.uk, have titles of 49, 55 and 52 characters and none carries a brand suffix. They sit right in or next to the band the Zyppy study found was rewritten least.
The point is not that those six pages were punished: they are all on page one. The point is that the text their click-through rate depends on was chosen by Google, not by them.
Six signs of over-optimisation and what each one risks
The lists going around put very different things on the same level. This table separates what breaches a spam policy from what simply costs you something.
| Sign | Breaches a spam policy? | What actually happens |
|---|---|---|
| Keyword repeated in the title and in every heading | No, if the page stays readable | Google rewrites the title and your CTR depends on text you did not choose |
| Lists of towns or variants at the bottom of the page | Yes: keyword stuffing, hidden text and link abuse | Possible manual action on those pages |
| All internal links with exact-match anchors | No | Pages cannibalise each other and the anchor stops carrying information |
| One page for every variant of the same query | No | Two weak pages instead of one strong one, and Google picks one itself |
| Bought links with commercial anchors | Yes: link spam | "Unnatural links to your site" manual action |
| Text mass-produced to cover lists of keywords | Yes, at scale: scaled content abuse | Deindexing of the pages involved |
The last row is the one changing fastest. According to the Office for National Statistics, in an article published on 20 July 2026 based on its Business Insights and Conditions Survey, self-reported use of AI among UK businesses with ten or more employees rose from around 12% in late 2023 to around 35% in June 2026. Among businesses with 250 or more employees it reached 49%. Producing text costs less and less, and scaled content abuse is the policy Google added for exactly this scenario. The dividing line is not the tool: we have collected what Google really says about AI-generated content and SEO.
Keyword density is not a number
The 2% threshold, the 3% one, the 10% ceiling: none of these figures appears in a Google document, and no study holds them up. They survive because they are easy to put in a checklist and because plugins show them with a traffic light.
The real numbers point the other way. On the 29 articles from our Italian blog where we counted the exact occurrences of the focus keyword, the median is 0.3% and none reaches 3%. In the US market, Rankability analysed 1,536 results across 32 competitive keywords and found an average density of 0.04% in positions 1 to 10, against 0.08% in positions 21 to 30: an American sample, so not a threshold to copy, but a clear shape. The pages higher up repeat less.
The check that works takes a minute: read the text aloud. Where you stumble, the keyword is one too many. Then look at where it appears: if it is in the title, the first paragraph and the places where it genuinely helps explain what you are talking about, you are writing. If it appears in every subheading and every anchor, you are filling in a form. On how to write a page that answers a query without turning into a list of repetitions, we have a dedicated guide to search intent and one on on-page SEO.
How to de-optimise a page
Five steps, in the order it makes sense to take them.
- Start from the data, not from a feeling. In Google Search Console look for pages with stable impressions and falling clicks. That is the typical profile of a page that still ranks but is no longer chosen. If impressions are falling too, the problem is ranking and the diagnosis changes: we have separated the two in the guide to traffic drops.
- Compare the SERP title with your title tag. Search for the page on Google and see what appears. If the text is different, Google has already decided your title was not good enough.
- Rewrite the title at 50 to 60 characters. The keyword once, the brand once or not at all, and in the space left, the reason someone should click on you rather than on the other nine.
- Vary your internal anchors. If twenty links point to the same page with the same exact phrase, change them: describe what the person clicking will find. The same goes for internal links in menus and footers, where the build-up goes most unnoticed.
- Merge twin pages. Two pages answering the same question take strength from each other. Keep the one with more inbound links, move the good parts of the other into it, and redirect.
The awkward one is the fifth. Deleting pages that someone worked on is a decision that gets put off, and it is why most SEO audits end up as a document rather than a different website.
The opposite case: less optimisation, more specificity
Macropix is an Italian manufacturer of custom LED screens, and in 2020 it did not appear for any category keyword in its sector. The work did not start from more optimisation: it started from the vocabulary industrial buyers actually search with. Of the nine keywords that now bring the company enquiries, none contains the company name, and the biggest is "ledwall", with 4,400 searches a month in Italy.
The site went from position 88 to position 2 for its main keyword. In July 2026, on the ledwall cluster, macropix.it had a 25.55% share of voice against 18.08% for amazon.it. The full story, with the competitor table, is in the guide to SEO for manufacturing.
What none of those pages does is repeat "ledwall" thirty times. They describe technical differences a buyer looks for and that almost no competitor puts in writing. It is the kind of work we do in our SEO consultancy projects, and in practice it looks more like a technical interview than an optimisation.
Why people end up overdoing it
An over-optimised page is almost always a page whose writer did not have much to say. The repeated keyword, the synonyms forced in, the twenty internal links with the same anchor: they fill a space the content could not fill on its own. When there is a number, a comparison or a procedure that works inside the page, optimisation comes down to a few things, and none of them looks like a trick.
If you have to pick one thing to do this week, take the ten pages with the most impressions and look at which title Google is showing in place of yours. It is the quickest way to find out where the search engine has already given its opinion of your work.
SEO over-optimisation FAQs
Not in itself. Google only takes action against the practices listed in its spam policies, such as keyword stuffing, link spam and scaled content abuse, and manual actions show up in the dedicated Search Console report. An overloaded title or too many identical anchors do not trigger a penalty: they cost you clicks, positions and clarity.
There is no threshold. Neither 2%, 3% nor 10% appears in any Google document. The useful check is to read the text aloud: if you stumble over a repetition, that repetition is one too many.
Because the title shown is the title link, which Google generates from seven sources: the title element, the main visible title, headings, og:title, large and prominent text, anchor text on the page and in inbound links. When it detects a problem, such as keyword stuffing or boilerplate titles, it rewrites it. In our check of 26 September 2026 on the nine organic results on page one of Google UK for "seo agency london", six titles out of nine differed from the page's title tag.
There is no limit. The sign of over-optimisation is not quantity but repetition: twenty links pointing to the same page with the same exact anchor remove information rather than add it, and set your pages against each other.
Three checks, in order. Search for the page on Google and see whether the title shown matches yours. Check in Search Console whether impressions stay stable while clicks fall. Read the page aloud and count how many times you stumble over the same word.
