SEO
The technical SEO fundamentals that decide whether a page can be found, crawled, indexed, and ranked at all, before content quality or AI search even enter the picture.
Search Engine Optimization is the practice of making a website easy for a search engine to find, understand, and consider worth showing to the person who typed a query. That's the whole job. Keywords, backlinks, and page speed all exist to serve one of those three things: findability, understandability, or worthiness.
A page that can't be crawled doesn't get indexed. A page that isn't indexed can't rank, no matter how well it's written. That's the part most advice skips past, and it's the part that actually breaks sites most often.
What Belongs Under SEO
Crawling & indexing. Before a page can rank, a search engine's bot has to find it, read it, and decide it's worth storing. A broken internal link, a misconfigured robots.txt, or JavaScript hiding content from a crawler can all keep a page invisible, even when it looks fine to a human visitor.
Core Web Vitals. Google's specific measurements of real page experience: how fast the main content shows up, how quickly the page responds to a click, and how much it visually shifts while loading. A genuine ranking factor, and a bigger conversion factor.
On-page fundamentals. Titles, headings, and canonical tags aren't decoration. They're how a search engine, and increasingly an AI system, figures out what a page is actually about, and which version to treat as the real one when duplicates exist.
Technical SEO. The broader mechanics search engines depend on to render and understand a site correctly: rendering, structured data, site architecture: the plumbing underneath everything else here.
The Order That Actually Matters
If a site has a real problem, it's almost always in this order: can it be crawled and indexed at all, is it fast enough not to lose people, and only then does on-page structure start to matter. Jumping straight to "on-page SEO" while a site has an indexing problem is a common, expensive mistake. New title tags don't help a page Google never sees.
How to Diagnose a Technical SEO Problem
Most technical SEO work isn't creative, it's diagnostic: finding which of a small number of known failure points is actually responsible before touching anything. A repeatable order, using Google Search Console as the primary source of truth rather than guesswork:
- Check Index Coverage first, not rankings. Search Console's Page Indexing report shows exactly why a URL isn't indexed:
Crawled – currently not indexed,Discovered – currently not indexed,Blocked by robots.txt,Excluded by noindex tag, andDuplicate without user-selected canonicalare the categories that actually explain most missing pages. Guessing at the cause before reading this report wastes time on the wrong fix. - Confirm the page is reachable and renders correctly. Use the URL Inspection tool's "Live Test" to see the page exactly as Googlebot renders it, not as it looks in a browser. A page that depends on client-side JavaScript to inject its main content can pass a human eyeball check and still render empty to a crawler. See JavaScript SEO for what Googlebot does and doesn't execute.
- Rule out a canonicalization conflict. If a page exists but a different URL is indexed instead, check for duplicate or near-duplicate content, an incorrect
rel=canonical, or parameter variants competing with the clean URL. This is a distinct failure mode from not being indexed at all. See canonical tags. - Check for accidental crawl blocks. A
Disallowrule left over from staging, anoindextag added during a redesign and never removed, or an AI-crawler block that was actually intended to also exclude Googlebot. See robots.txt and AI crawlers for exactly which directive controls which behavior, since the names are easy to confuse. - Only then look at Core Web Vitals and on-page structure. These affect how well an already-indexed page performs, not whether it gets indexed in the first place. Checking them before ruling out steps 1–4 is a common way to spend a week improving something that wasn't the actual problem.
Common Technical SEO Mistakes
A handful of failure patterns account for most real technical SEO problems, and they tend to recur across otherwise very different sites:
- Redirect chains that quietly bleed link equity. Every additional hop in an A→B→C redirect chain adds a small amount of signal loss and page-speed cost. Sites that have gone through multiple redesigns or domain moves without cleaning up old redirects accumulate these silently. See 301 redirects and link equity for what the evidence actually shows about how much is lost, rather than the inflated numbers that circulate informally.
- Crawl budget wasted on low-value URLs. Faceted navigation, internal search result pages, and near-duplicate parameter URLs can consume a disproportionate share of a large site's crawl budget, leaving genuinely new or updated pages crawled less often. Log file analysis is the only way to see this directly. See crawl budget and log files.
- A page that's indexed but never ranks for anything. Not every indexing problem is a crawl problem. A page can be fully indexed and still fail to rank because it doesn't sufficiently differentiate itself from a stronger, more established page already answering the same query. See indexed but not ranking for how to tell the difference.
- Structured data that validates but doesn't help. Schema markup that's technically valid but uses a type Google no longer surfaces as a rich result is effort spent for no visible return. See which schema types still produce rich results for what's actually current.
New to any of this? Start with crawling vs. indexing. Nearly every other technical SEO problem downstream assumes that distinction is already clear.
Thirteen deep-dive guides are published so far, listed below in the order they go deeper into each piece: crawling and indexing, robots.txt and AI crawlers, JavaScript rendering, crawl budget and log files, canonical tags, Core Web Vitals, indexed but not ranking, 301 redirects and link equity, structured data and AI citations, which schema types still produce rich results, do sitemap priority and changefreq tags actually matter, nofollow, sponsored, and ugc link attributes explained, and does rel=next/prev still matter for pagination SEO.
Looking for the AI-search side of this: AEO, GEO, AI Overviews? See AI Search.
Go deeper
Crawling vs. Indexing: The Difference That Actually Matters
Crawling and indexing aren't the same step, and mixing them up leads to the wrong fix. Here's what each one actually means, including what Google's own Search Console statuses do and don't tell you.
Why robots.txt Silently Blocks AI Crawlers (and How to Verify Yours Isn't)
robots.txt is a text file that tells crawlers which parts of a site they may access. But "may access" doesn't mean the same thing to every AI system, and getting this precise matters more than copying a template file.
JavaScript SEO: What Googlebot Renders, What AI Crawlers Don't
Googlebot renders JavaScript. Most AI crawlers don't. What that gap actually means for a JS-heavy site.
Crawl Budget and Log Files: What They Prove and What They Can't
Server logs show exactly what a crawler did, not why. What log-file analysis can and can't tell you.
Canonical Tags and Canonicalization Explained
How canonical tags tell search engines which version of a page is the real one, and where they get misused.
Core Web Vitals in 2026: What's Actually True (and What's a Myth Right Now)
Real LCP, INP, and CLS thresholds, checked against Google's own current documentation.
Indexed But Not Ranking: What Google Search Console Is Actually Telling You
A page can be indexed and still invisible in results. What that Search Console status actually means.
How Much Link Equity Do 301 Redirects and Redirect Chains Really Lose?
Google says 301s don't lose PageRank anymore. That's real, and it's not the whole story: what redirect chains, irrelevant destinations, and timing actually cost.
Structured Data Isn't a Ranking Factor: So Why Does It Keep Winning AI Citations?
Google says schema markup isn't a ranking signal. The evidence for why it still matters for AI citations.
Which Schema Types Actually Still Produce Rich Results in 2026
Not every schema type Google once supported still produces a visible rich result. What still works, and what happened to FAQ schema.
Do Sitemap Priority and Changefreq Tags Actually Matter to Google?
The sitemap protocol has four fields. Google's own documentation says it ignores two of them entirely, and only conditionally trusts a third.
Do rel=nofollow, sponsored, and ugc Links Still Work the Way You Think?
Nofollow stopped being a directive in 2020. Most explanations of these link attributes still describe the old rule, not the current one.
Does rel="next"/"prev" Still Matter for Pagination SEO?
Google quietly stopped using rel=next and rel=prev years before it said so publicly. A lot of pagination advice still treats them as a working signal.
Frequently asked questions
What's the actual difference between technical SEO and on-page SEO?
Technical SEO covers whether a search engine can crawl, render, and index a page at all: robots.txt, JavaScript rendering, canonical tags, site architecture. On-page SEO covers how well an already-indexed page communicates what it's about: titles, headings, content depth. A page can be perfectly optimized on-page and still never rank if a technical issue keeps it out of the index in the first place, which is why technical issues get fixed first.
Why is my page indexed but not ranking for anything?
Being indexed only means Google has stored a copy of the page; it says nothing about whether that page is considered the best answer for any given query. The two most common causes are content that doesn't sufficiently differentiate itself from an already-dominant competing page, and a canonicalization conflict sending ranking signal to a different URL than the one meant to rank. See indexed but not ranking for the full diagnostic path.
Do Core Web Vitals actually affect rankings?
Google's own documentation states plainly that Core Web Vitals are used by its ranking systems, and separately states that a good score alone doesn't guarantee top rankings. In practice, they function as a real but secondary signal, most useful as a tiebreaker between pages that are already answering a query about equally well, not as a substitute for content that answers the query at all.
How long does it take for a technical SEO fix to show results?
It depends entirely on what was fixed. Removing a robots.txt block or a noindex tag can lead to recrawling within days once resubmitted in Search Console, but a full ranking response, if any, typically takes weeks as Google reassesses the page against competing results. Fixes to crawl budget or site-wide canonicalization issues on larger sites can take longer simply because there's more to recrawl.
Can AI crawlers see my site if Googlebot can?
Not automatically. Googlebot, GPTBot, ClaudeBot, and PerplexityBot are separate crawlers with independently configurable robots.txt rules, and a site can allow one while blocking another without realizing it. See robots.txt and AI crawlers for exactly which bot controls what, since names like Google-Extended are commonly misread as crawlers when they're actually permission flags on content Googlebot already fetched.
Want this applied to your own site, not just read about it?
This is the free version, evidence-labeled and yours to read at no cost. Applying it to your own site (technical SEO, AI search visibility, and GEO in one pass) is separate, paid work at kuraib.site.