Technical SEO Audit Checklist: What We Examine on Every Client Site
Written by Gabriel Bertolo
June 15, 2026
96% of web pages get zero traffic from Google.
The difference between the 4% that get traffic and the 96% that don’t usually comes down to technical SEO. Not content. Not backlinks. The invisible infrastructure underneath the site determines whether search engines can even read it.
Technical SEO is the practice of optimizing a website’s infrastructure so that search engines can crawl, render, index, and rank its pages. It has nothing to do with how good your writing is or how many sites link to you. It’s about machine accessibility. It’s about making sure nothing is quietly standing between your best pages and the search engines trying to read them.
And here’s what makes it sneaky. When your site fails Core Web Vitals, you don’t just rank lower. You lose up to 60% of your visitors who won’t sit there waiting for a page to load. When crawlers can’t index a page, your best work simply doesn’t exist as far as Google is concerned. Most business owners have no idea any of this is happening until their traffic falls off a cliff, and by then, they’ve already lost months of revenue they’re never getting back.
I’ll be honest about something. Finding these problems is the part of this job I actually enjoy. There’s a particular satisfaction in pulling apart a site that’s been mysteriously underperforming and finding the one broken thing nobody else caught. It’s detective work. And the culprit is almost never where the client expects.
At Radiant Elephant, our technical SEO audits go deep. We don’t run a Screaming Frog report and call it a day, because the automated tools miss things. We examine over 100 technical factors, and we rate every issue by priority, severity, and the revenue it’s costing you.
When I audit a new client’s website, whether it’s a restaurant here in Northampton, a contractor out in the Pioneer Valley, or a shore business down in Asbury Park, I usually find 30 to 50 technical issues within the first hour. That’s the average. And it holds whether the site was thrown together by a freelancer or built by a giant national agency charging five figures.
This article breaks down what a real technical SEO audit covers, why each piece matters for rankings and for the people actually using your site, the tools we use, the problems we see most, and how all of it connects back to your bottom line. By the end, you’ll understand why this stuff is the foundation everything else sits on.
Only 54.6% of websites pass all three Core Web Vitals assessments. Source: SE Ranking
That number gets uglier on mobile, where the majority of your visitors actually are.
Just 43.4% of websites pass the mobile Core Web Vitals test. Source: SEO Sherpa
Core Web Vitals are the three metrics Google uses to measure real user experience. They’re worth understanding because they sit at the intersection of rankings and revenue.
One important update before we go further. In Google’s March 2026 core update, the “Good” threshold for Largest Contentful Paint tightened from 2.5 seconds to 2.0 seconds. A lot of sites that were comfortably passing in February got quietly downgraded in March without anyone telling them. If your audit data predates that change, it’s already stale.
What it measures: The time until the largest visible element loads, which is usually your hero section. As of the March 2026 update, the target is under 2.0 seconds.
Why it matters: People judge your speed by how long it takes to see the main content, not by when the page technically finishes loading. A slow LCP means people bail before they ever see your message. They’re not patient. They’re sitting at a red light or standing in a checkout line, and if your hero image hasn’t shown up, they’re gone.
Common issues: Unoptimized images, no lazy loading, render-blocking JavaScript and CSS, slow server response from cheap hosting, and no CDN like Cloudflare.
Business Impact: Sites that take over 2 seconds to load lose 60% of their visitors. Source: Hostinger.
If you’re pulling 10,000 visitors a month, a slow LCP could be bleeding 6,000 potential customers before they read a single word.
Tools we use: Chrome DevTools, Google PageSpeed Insights, GTmetrix, plus testing on real devices and real connections.
What it measures: How fast the page responds when someone clicks, taps, or types. The target is under 200 milliseconds.
Why it matters: An unresponsive site feels broken in a way people can’t always articulate but absolutely feel. They tap a button and nothing happens. A menu freezes for half a second. A form lags. It creates this low-grade frustration that makes someone trust your business a little less without even knowing why.
Common issues: Heavy JavaScript blocking the main thread, third-party scripts like chat widgets and analytics causing delays, unoptimized event handlers, and long tasks that block interaction.
Business Impact: On e-commerce sites, a sluggish INP loses sales right at checkout. For service businesses, a laggy form loses the lead. The difference plays out in milliseconds, but the revenue impact is real.
What it measures: How much the page jumps around while it loads. The target is under 0.1.
Why it matters: You know the feeling. You go to tap a button, the page shifts at the last second, and suddenly you’ve tapped an ad instead. That’s CLS in action, and it’s maddening. Every one of those little betrayals chips away at how much someone trusts your site.
Common issues: Images without width and height attributes, ads and embeds without reserved space, web fonts that shift the text as they load, and content injected dynamically that shoves everything else down.
Business Impact: A bad CLS score quietly kills conversions. If a customer has to chase a button around the screen, whatever trust you’d built evaporates.
68% of WordPress sites fail CLS. Source: Loopex Digital.
The usual culprit is a poorly built theme or a pile of plugins fighting each other.
For a deeper look at how all of this plays out on phones specifically, we wrote a whole piece on mobile-first web design.
You can have the best content in your market, the sharpest value proposition, and on-page SEO dialed in to the last detail. None of it matters if search engines can’t crawl and index the site. This is the category that breaks my heart the most, because the problems here are so often invisible and so often catastrophic.
52% of sites misconfigure their robots.txt files. Source: SEOMator.
That means a lot of businesses are blocking their own money pages without the faintest idea they’re doing it.
A robots.txt file is a plain text file in your site’s root directory that tells search engine crawlers which URLs they can and can’t access. It manages crawl budget and keeps crawlers out of non-public or duplicate sections.
What we check: That the file exists and is reachable, that it isn’t blocking important pages, crawl-delay directives, whether the sitemap location is declared, and that it isn’t accidentally blocking CSS or JavaScript.
Common errors: Inexperienced agencies blocking an entire site with a single “Disallow: /” line. Sites blocking both /wp-admin/ and /wp-content/, which takes all the images and CSS down with it. Blocking JavaScript so Google can’t properly render the page.
Business Impact: A page blocked by robots.txt won’t rank. It’s completely invisible to search engines, full stop.
I’ve watched this play out more than once, and it never stops being painful. A client comes to me frustrated and a little panicked. They redesigned their website and their traffic is in free fall. I pull up the site, check the robots.txt, and there it is. The entire website is set to disallow. Every page. It’s a rookie mistake, but it happens far more often than you’d believe, and the people it happens to are rarely the ones who made it.
An XML sitemap is a structured file listing your site’s important URLs so search engines can find and crawl them efficiently. You submit it through Google Search Console, where it signals your canonical pages, update frequency, and last-modified dates.
What we examine: That a sitemap exists and is submitted, that it includes all your important pages, that it excludes blocked or noindexed pages, that there are no redirecting URLs in it, that it stays under 50MB and 50,000 URLs, and that it’s formatted correctly.
Common issues: Sitemaps stuffed with URLs that 404, redirect, or point to noindexed pages. Missing sitemap references in robots.txt. Sitemaps never submitted to Search Console. Low-value pages like tag archives and author pages cluttering it up. High-value pages missing entirely.
Business Impact: Your sitemap is how you tell Google which pages matter. If your priority pages aren’t in it, you’re leaving them to chance.
A page is indexable when it returns a 200 status code, allows crawling, and avoids noindex directives or canonical conflicts. Get this wrong and your page can’t rank, period.
What we audit: That pages meant to rank aren’t noindexed, that canonical tags point to the right versions, that there are no canonical-versus-noindex conflicts, that there are no orphaned pages, that the URL structure is clean, and that excessive URL parameters aren’t spawning duplicate content.
Common problems: Staging noindex tags left on the live site. Canonical tags pointing at the wrong pages. Important pages accidentally set to noindex. Infinite scroll that isn’t crawlable. Content trapped behind login walls or inside iframes.
Here’s the one that genuinely keeps me up at night. At least three separate times, I’ve audited a site where the development team left the noindex tags from the staging build on the production site. Three times. The sites had been live for months, pulling in zero organic traffic, and the owners were completely baffled about why their traffic vanished after the redesign. One meta tag. A single line of code a developer forgot to remove. And it cost those businesses hundreds of thousands of dollars in revenue they’ll never see. That’s the thing about this work. The smallest oversights do the most damage, and the people paying the price usually never even knew the risk existed.
Tools we use: Screaming Frog crawls, the Search Console coverage report, manual review of critical pages, and indexation spot-checks.
Site architecture is how you organize and connect the pages on your site. A clean architecture sorts content into logical categories, and internal links pass authority around while guiding crawlers to what matters. This is the category I genuinely geek out on, because internal linking is one of the most underrated levers in all of SEO, and almost nobody does it well.
Click distance is how many clicks it takes to reach a page from the homepage. Shallow is better. Important pages should sit three clicks or fewer from home.
What we measure: Clicks from the homepage to your important pages, orphaned pages with no internal links pointing to them, the depth of your site hierarchy, and how clear your navigation actually is.
Every click further from the homepage means less crawl priority and weaker rankings. To Google, distance from the homepage is a rough proxy for importance.
Common mistakes: Blog posts buried five or more clicks deep. Service pages reachable only through layers of navigation. Key landing pages left out of the main nav entirely. No internal links connecting related content.
Business Impact: A page with high click distance rarely ranks well, even when the content is genuinely excellent. The further it sits from home, the less Google cares.
Internal links connect pages on the same domain. They help search engines discover content, understand how your topics relate, and distribute PageRank across your URLs. Strategic anchor text clarifies context and strengthens relevance.
What we audit: Anchor text distribution, how link equity flows to priority pages, related-content linking, breadcrumb implementation, footer and sidebar links, and broken internal links.
This is where the real fun is. Strategic internal linking spreads PageRank through the whole site, so everything ranks better. Poor linking starves your most important pages of the authority they need.
52% of websites have broken links that create dead ends, waste crawl budget, and erode trust.
When we work on this, we don’t just sprinkle in more links and hope. We map out how authority actually flows through the site. Priority pages earn links from high-authority, topically relevant pages with anchor text chosen on purpose. We link content clusters together to build genuine topical authority. Every link has a job.
For larger sites, crawl budget enters the picture. It’s a non-issue for small sites, but a big site can waste its entire crawl budget on low-value pages while the revenue pages go unnoticed. When that happens, we restructure to point the crawl budget where the money is.
Google uses mobile-first indexing, which means it primarily evaluates the mobile version of your site for ranking. If your mobile experience is rough, your rankings will be too, even for the people visiting on desktop.
I’ll be precise here, because this point gets badly overstated around the web. After July 5, 2024, Google moved to crawling with the smartphone bot only. What that actually means is that a site whose content is completely inaccessible on a mobile device will no longer be indexed. It does not mean that a desktop-oriented site automatically gets dropped. If your content loads and is reachable on a phone, you’re still indexed. The sites that got cut were the ones that genuinely don’t function on mobile at all, which is a small slice of the web. The accurate takeaway is that mobile accessibility is now a hard requirement, and mobile quality heavily shapes your rankings.
Since we go deep on this in our mobile-first web design guide, I’ll keep this section focused on what we specifically check during an audit.
What we verify: That the site renders correctly on real phones, that responsive design is properly implemented, that there are no mobile usability errors in Search Console, that the mobile content matches desktop (Google indexes the mobile version), and that there are no intrusive full-screen pop-ups on mobile.
Common critical issues: Text too small to read on the “responsive” sites that aren’t truly responsive. Tap targets crammed too close together, below the 44 by 44 pixel minimum. Horizontal scrolling. Mobile content hidden or stripped down from desktop. Viewport configured wrong.
Business Impact: Mobile-friendly websites are 67% more likely to rank on the first page. Source: PageOptimizer Pro.
A competitor with a genuinely better mobile experience can outrank you even when your content and your off-page SEO are stronger.
Why mobile speed is harder: Phones deal with slower connections than WiFi and have far less processing power.
53% of mobile users abandon a site that takes more than 3 seconds to load. Source: DesignRush.
If your mobile site takes 5 seconds, more than half your traffic is gone before they see anything.
We test on PageSpeed Insights and GTmetrix, then verify on real devices on real networks. Simulators are useful, but they miss things that only show up on an actual phone on actual cell service.
These are the HTML and code-level pieces that help search engines interpret your pages. Title tags, meta descriptions, headers, canonicals, structured data, alt text, status codes. The fundamentals. And the fundamentals are exactly where the expensive mistakes hide.
Title tags define a page’s title and show up as the clickable headline in search results. Google uses them to understand what a page is about.
What we audit: That every page has a unique title, that titles stay under 60 characters to avoid truncation, that the target keyword is included naturally, that brand placement makes sense, and that no titles are duplicated.
54% of websites use duplicate title tags. When that happens, Google has to guess what each page is about, and a guessing search engine is never working in your favor.
This problem is everywhere, and it shows up in places you’d never expect. I worked on an SEO recovery for a large national brand whose site had been redesigned by a well-known national agency. The redesign cost them well over $30,000. And when I dug in, I found hundreds of pages with duplicate meta titles and duplicate meta descriptions. I genuinely sat there for a second in disbelief. Thirty thousand dollars, a name-brand agency, and they shipped a site with the most basic on-page error in the book.
Common problems: The same title on 50-plus pages. Keyword-stuffed titles. Missing titles. Titles so long Google chops them off mid-sentence. ALL CAPS titles that read like spam.
Business Impact: The title tag is the single most important on-page ranking factor. Leaving it empty or sloppy has a direct, measurable effect on where you rank.
Meta descriptions summarize a page’s content beneath the title in search results.
Quality checks: Unique descriptions per page, 150 to 160 characters, target keywords included (Google bolds them in the SERPs), written to earn the click with a real call to action, and not keyword-stuffed.
50% of websites have duplicate meta descriptions, which flattens click-through rates. Your meta description is your one shot at an elevator pitch in a results page full of competitors. It has to make someone choose you.
Header tags from H1 to H6 organize your content’s structure. Search engines read them to understand your topic and subtopics, and people read them to skim.
Hierarchy audit: One H1 per page containing the primary keyword, a logical H2 through H6 structure, no skipped levels, headings that actually describe their sections, and keywords integrated naturally rather than forced.
Common mistakes: Multiple H1s diluting the focus. No H1 at all. Headers are used for styling instead of structure. Long content with no headers to break it up. The same keyword is jammed into every heading. Random header levels jumping from H2 to H4 to H5 in no sensible order.
Nearly every page ranking on page one uses its target keyword in the H1. It’s that consistent.
Image optimization is about how fast images load and how well they communicate context to search engines.
Checklist: Descriptive alt text on every image, real filenames instead of IMG_1234.jpg, compressed file sizes, proper dimensions instead of giant images scaled down with CSS, next-gen formats like WebP, and lazy loading.
A few numbers worth knowing: image search makes up 22.6% of all Google queries, sites with descriptive alt tags see a 23% bump in organic traffic, only 26% of sites use alt text properly, and 36% of sites are serving oversized images that drag down their speed.
Business Impact: Bad or missing alt text leaves ranking potential and accessibility on the table. Oversized images slow the whole site down, which hurts rankings and conversions together. We run images through Imagify for compression and WebP conversion, and our WordPress framework handles lazy loading and alt text.
Schema markup is standardized code that helps search engines understand the entities on your page and how they relate. You implement it with JSON-LD to define things like articles, products, reviews, and organizations. Done right, it earns rich results and clears up ambiguity about who you are and what you do.
72.6% of the results on page one use Schema markup. It’s that common among the pages that win.
Instead of forcing Google’s bots to crawl your entire page and infer meaning, schema hands them a clean, labeled snapshot. It reinforces your location, your awards, your E-E-A-T signals, and your keywords. It links you to your Google Maps listing, your most authoritative citations, your social profiles, and the Wikipedia entities that define your services.
Here’s my favorite way to explain what it solves. Take the word “fencing.” It can mean the barrier around your yard, the Olympic sport with the swords, or the act of selling stolen goods. If a company teaches the sport, schema removes all doubt by linking directly to the Wikipedia entity for fencing the sport. No ambiguity. Google knows exactly what you are.
Rich results it enables: Star ratings, product prices and availability, recipe times, event dates, FAQ dropdowns, video thumbnails, breadcrumb trails, and local business info like hours and address.
A few numbers: sites with structured data are 58% more likely to earn rich snippets, rich snippets lift CTR by 20 to 35%, and users click rich results 58% of the time versus 41% for plain results.
Real Example: A client was sitting in the middle of page one. We added LocalBusiness schema with ratings, service area, and the rest. Within a few days, their CTR jumped from 3.7% to 10.3%. Same ranking position. Nearly three times the clicks. That’s the power of standing out in a sea of plain blue links.
We prioritize Organization and LocalBusiness schema for company identity, and this one gets genuinely intricate when we layer in the knowsAbout, mentions, and sameAs properties. Article and BlogPosting schema powers Google News, Discover, and AI citations. Product schema is essential for e-commerce, where complete markup makes a product 4.2 times more likely to show up in Google Shopping. Service schema lets us define exactly what we offer and where. Then there’s FAQ, Review and AggregateRating, Breadcrumb, HowTo, Event, and Video schema, each one unlocking its own search feature.
The reason we use multiple types is that comprehensive markup builds a connected web of entities and relationships. Google stops seeing isolated pages and starts understanding how your whole site fits together. We implement everything in JSON-LD, the format Google recommends, because it’s cleaner and easier to maintain than the alternatives.
We validate every schema type with Google’s Rich Results Test, check syntax with the Schema Markup Validator, watch the Search Console Enhancements report for warnings, and do manual SERP checks to confirm rich results are actually showing.
One thing people forget: schema isn’t something you set once and walk away from. It needs updating whenever your prices, services, contact info, URLs, or business details change. Outdated schema can cost you your rich results, and losing those costs you clicks.
95% of Google’s top results use HTTPS. Non-secure sites carry 50% higher bounce rates, and browsers flag HTTP pages as “Not Secure.”
An SSL certificate authenticates your site’s identity and enables HTTPS encryption, protecting the data passing between the browser and your server.
What we verify: A valid SSL certificate, all pages loading over HTTPS, no mixed-content warnings, working HTTP-to-HTTPS redirects, an unexpired certificate, and coverage for every subdomain you need.
Common problems: Some pages still serving HTTP. Images, CSS, or JavaScript loading over HTTP and triggering mixed-content warnings. Canonical tags or internal links pointing to HTTP versions. Sitemaps referencing HTTP URLs. Expired certificates.
Business Impact: A “Not Secure” warning destroys credibility in an instant. Most people won’t type their information into a site flagged as unsafe, and Google uses HTTPS as a ranking factor, so non-secure sites rank lower on top of it.
Security headers are HTTP response directives that protect against common attacks. Content-Security-Policy, Strict-Transport-Security, X-Content-Type-Options, X-Frame-Options. They guard against cross-site scripting, clickjacking, MIME sniffing, and downgrade attacks.
What we check: CSP headers, X-Frame-Options to stop clickjacking, X-Content-Type-Options to stop MIME sniffing, a configured Referrer-Policy, and HSTS.
These aren’t direct ranking factors, but they prevent the kind of security incident that obliterates rankings overnight. And on that note, I want to be serious for a moment, because this is the part of an audit where the stakes get real. A hacked site can get deindexed entirely, or start loading with a warning that it may be compromised. When that happens, traffic doesn’t dip. It goes to zero. Overnight. And recovery can drag on for weeks while you scrub every trace of malware and beg Google to reconsider. I’ve seen the panic in a business owner’s voice when this happens to them. Prevention costs a tiny fraction of recovery, and it’s one of the few places in this work where an ounce of caution genuinely saves a livelihood. Keep your plugins updated, since 90% of WordPress hacks exploit outdated ones. Use strong passwords, two-factor authentication, limited permissions, daily backups, and regular scanning.
Our audit runs on a mix of automated tools and manual review, because neither one alone is enough. We usually start with a full crawl in Screaming Frog or SiteBulb to map the basics, which almost always surfaces threads worth pulling on. Then we load the site into Ahrefs for a health check and ongoing monitoring, and head into Google Search Console to check indexation status, look for manual actions, and review the coverage data.
For crawling and analysis, we lean on Screaming Frog for full-site crawls, Ahrefs Site Audit for automated health monitoring and 100-plus checks, and Google Search Console for indexation, coverage errors, mobile usability, Core Web Vitals, and manual actions. For performance, we use PageSpeed Insights, GTmetrix, and WebPageTest. For mobile, the Google Mobile-Friendly Test, BrowserStack for real-device testing, and Chrome DevTools. For schema, the Rich Results Test and the Schema Markup Validator. For security, SSL Labs, SecurityHeaders.com, and Sucuri SiteCheck.
No single tool catches everything, and that’s not a knock on any of them. Screaming Frog misses things Search Console surfaces. PageSpeed Insights and GTmetrix report different data on the same page. A thorough audit cross-validates across 10 to 15 tools so nothing slips through.
We run a full automated crawl on day one and pull in the Ahrefs and Search Console data. Days one and two go to performance analysis on the top 20 pages across PageSpeed Insights, GTmetrix, and WebPageTest, documenting the Core Web Vitals patterns. Days two and three are manual review: robots.txt, sitemaps, critical pages, indexation coverage, mobile experience on real devices, schema validation, and security headers. Day three is a competitive comparison, where we audit the top three competitors’ technical SEO to find the gaps and the openings. Then days four and five are prioritization and reporting, where we sort every issue by severity, estimate the business impact, and build an action plan with a timeline.
The deliverable is a 20 to 50 page report with an executive summary focused on business impact, a severity breakdown, category-by-category findings, the competitor comparison, a prioritized action plan, effort estimates, and projected traffic and ranking impact.
Here’s why we go to this length. A lot of less experienced SEOs run one tool, export the report, and hand it over. That’s not an audit. That’s a data dump. We do all of this so we know every issue that exists, why it exists, and exactly what it’s costing you, which lets us sequence the fixes for the fastest possible results. Our audits are strategic documents, not vague problem lists.
This checklist is one piece of a much larger strategy. For the full picture, read our complete SEO guide. And if technical issues are part of getting you ready for AI search, see how we prepare websites for AI search visibility.
If your traffic has dropped or your site just isn’t ranking the way it should, a technical audit is very often the thing that finds out why. We do this work for businesses across Western Massachusetts, down the Jersey shore, and well beyond both. Reach out through our contact form and let’s find out what’s actually holding your site back.
Gabriel Bertolo is a 3rd generation entrepreneur who founded Radiant Elephant over 13 years ago after working for various advertising and marketing agencies.
He is also an award-winning Jazz/Funk drummer and composer, as well as a visual artist.
His Web Design, SEO, and Marketing insights have been quoted in Forbes, Business Insider, Hubspot, Entrepreneur, Shopify, MECLABS, and more.
Check out some publications he's been quoted in:
Quoted in HubSpot's AI Search Visibility Article and HubSpot's Article on 6 Best Wix Alternatives
Quoted in DesignRush Dental Marketing Guide
Quoted in MECLABS
Quoted in DataBox Website Optimization Article and DataBox Best SEO Blogs
Quoted in Seoptimer
Quoted in Shopify Blog