How to Conduct a Technical SEO Audit: Step-by-Step Guide for 2025

Technical SEO is the foundation on which all other SEO work rests. You can produce the best content in your industry, earn high-quality backlinks, and still fail to rank if search engines cannot correctly crawl, index, and understand your site.

A technical SEO audit systematically checks every factor that affects a search engine's ability to discover, process, and rank your pages. This guide walks through the complete audit process, explains what to look for at each step, and shows how to use SiteReveal to automate much of the detection work.

What a Technical SEO Audit Covers

A thorough technical SEO audit examines six areas:

SiteReveal's SEO dimension (20% of your WIS) automatically checks most of these signals during a scan. This guide explains what each check means and what to do when it fails.

Step 1: Audit Crawlability

Search engines discover your pages by following links from a starting point (usually your homepage or sitemap). Crawlability problems prevent them from finding pages at all.

Check Your robots.txt

Your robots.txt file tells crawlers which parts of your site they can and cannot access. A misconfigured robots.txt is one of the most common causes of unexpected ranking drops — a single line can accidentally block your entire site from being indexed.

How to check: Visit https://yoursite.com/robots.txt and review the directives. Look for:

• Disallow: / — this blocks all crawlers from all pages (catastrophic if unintentional)
• Disallow: /blog/ or other important sections being blocked
• A Sitemap: directive pointing to your XML sitemap

SiteReveal detection: The scanner fetches and parses your robots.txt, flagging any Disallow directives that block important content.

Verify Your XML Sitemap

An XML sitemap is a file that lists all the URLs you want search engines to index, along with metadata about each page (last modified date, change frequency, priority).

Requirements for a valid sitemap:

• Must be accessible at /sitemap.xml or declared in robots.txt
• Must contain only canonical, indexable URLs (no noindex pages)
• Must be under 50MB and 50,000 URLs (split into multiple sitemaps if larger)
• Must be submitted to Google Search Console

Common mistakes:

• Including URLs that return 404 or redirect
• Including pages with noindex meta tags
• Not updating the sitemap when new content is published

Step 2: Audit Indexability

Crawlability is about whether search engines can reach your pages. Indexability is about whether they should include those pages in their index.

Check for noindex Tags

The <meta name="robots" content="noindex"> tag tells search engines not to include a page in their index. This is useful for admin pages, thank-you pages, and duplicate content — but devastating if applied to pages you want to rank.

How to check: In Chrome DevTools → Elements, search for <meta name="robots". Or use SiteReveal's scan, which checks the robots meta tag for every page it crawls.

Audit Canonical Tags

The canonical tag (<link rel="canonical" href="...">) tells search engines which version of a page is the "master" version when multiple URLs serve similar content. Incorrect canonical tags can cause your most important pages to be ignored in favour of duplicates.

Common canonical problems:

• Self-referencing canonicals pointing to the wrong URL (e.g., HTTP instead of HTTPS)
• Paginated pages all canonicalising to page 1
• Canonical pointing to a redirected URL

Step 3: Audit On-Page SEO Signals

Once you have confirmed that your pages are crawlable and indexable, audit the on-page signals that tell search engines what each page is about.

Title Tags

The title tag is the most important on-page SEO element. It appears in search results as the clickable headline and is a primary ranking signal.

Requirements:

• Unique for every page
• Between 50–60 characters (longer titles are truncated in search results)
• Contains the primary keyword for the page
• Accurately describes the page content

SiteReveal detection: The scanner checks for the presence, length, and uniqueness of title tags across your site.

Meta Descriptions

Meta descriptions do not directly affect rankings, but they appear in search results and significantly affect click-through rate. A compelling meta description can increase organic traffic even without a ranking improvement.

Requirements:

• Unique for every page
• Between 120–160 characters
• Contains a clear value proposition and a call to action
• Accurately summarises the page content

Open Graph Tags

Open Graph tags control how your pages appear when shared on social media (Facebook, LinkedIn, Twitter/X). Without them, social platforms generate their own previews — often poorly.

Essential Open Graph tags:

<meta property="og:title" content="Page Title">
<meta property="og:description" content="Page description">
<meta property="og:image" content="https://yoursite.com/og-image.jpg">
<meta property="og:url" content="https://yoursite.com/page">
<meta property="og:type" content="website">

<meta property="og:title" content="Page Title">
<meta property="og:description" content="Page description">
<meta property="og:image" content="https://yoursite.com/og-image.jpg">
<meta property="og:url" content="https://yoursite.com/page">
<meta property="og:type" content="website">

SiteReveal detection: The SEO dimension checks for the presence of all five essential Open Graph tags.

Heading Structure

Your page should have exactly one <h1> tag containing the primary keyword, followed by <h2> and <h3> tags that structure the content logically. Heading structure helps both search engines and users understand the hierarchy of your content.

Step 4: Audit Structured Data

Structured data (schema markup) is machine-readable metadata that tells search engines specific facts about your content — that a page is a product, a recipe, an article, a local business, or a FAQ. Well-implemented structured data can earn rich snippets in search results, which significantly increase click-through rates.

Most Valuable Schema Types

How to Implement

Use JSON-LD format (Google's recommended approach) in a <script type="application/ld+json"> tag in your page <head>:

{
  "@context": "https://schema.org",
  "@type": "Article",
  "headline": "How to Conduct a Technical SEO Audit",
  "author": {
    "@type": "Organization",
    "name": "SiteReveal"
  },
  "datePublished": "2025-01-15",
  "description": "A step-by-step guide to technical SEO auditing."
}

{
  "@context": "https://schema.org",
  "@type": "Article",
  "headline": "How to Conduct a Technical SEO Audit",
  "author": {
    "@type": "Organization",
    "name": "SiteReveal"
  },
  "datePublished": "2025-01-15",
  "description": "A step-by-step guide to technical SEO auditing."
}

Validation: Use Google's Rich Results Test to verify your structured data is valid and eligible for rich snippets.

Step 5: Audit Core Web Vitals

Google uses Core Web Vitals as a ranking signal. Pages that fail the thresholds are at a disadvantage in competitive search results.

The most reliable source of Core Web Vitals data is Google Search Console → Core Web Vitals report, which shows field data from real Chrome users. For sites without enough traffic for field data, Google PageSpeed Insights provides lab measurements.

For a detailed guide to improving each metric, see our Website Speed Optimisation guide.

Step 6: Audit Mobile Usability

Google uses mobile-first indexing, meaning it primarily uses the mobile version of your site for ranking. A site that works perfectly on desktop but is broken on mobile will underperform in search results.

Key mobile usability checks:

• Viewport meta tag is present: <meta name="viewport" content="width=device-width, initial-scale=1">
• Text is readable without zooming (minimum 16px font size for body text)
• Tap targets (buttons, links) are at least 48×48px
• Content does not overflow the viewport horizontally
• No intrusive interstitials (pop-ups that cover the main content on mobile)

How to check: Google Search Console → Mobile Usability report, or Chrome DevTools → Toggle device toolbar.

Automating Your Technical SEO Audit with SiteReveal

Running a manual technical SEO audit is time-consuming. SiteReveal automates the detection of most technical SEO signals in a single scan, giving you:

• SEO dimension score — an overall measure of your technical SEO health
• Signal evidence table — a checklist of every SEO signal checked and whether it passed or failed
• Prioritised recommendations — specific fixes ordered by their expected impact on your score
• Historical tracking — monitor your SEO health over time and catch regressions after deployments

Run a free technical SEO scan to get your site's SEO dimension score and a prioritised list of issues to fix.

Technical SEO Audit Checklist Summary

Use this checklist to track your audit progress:

Crawlability

• robots.txt is correctly configured and does not block important pages
• XML sitemap is present, valid, and submitted to Google Search Console
• No crawl errors in Google Search Console

Indexability

• No unintentional noindex tags on important pages
• Canonical tags are correct and self-referencing
• HTTPS is enforced with a redirect from HTTP

On-Page Signals

• Every page has a unique, appropriately-length title tag
• Every page has a unique meta description
• Open Graph tags are present on all pages
• Heading structure is logical (one H1 per page)

Structured Data

• Article/BlogPosting schema on blog posts
• BreadcrumbList schema on all pages
• Validated with Google's Rich Results Test

Performance

• LCP under 2.5 seconds
• INP under 200ms
• CLS under 0.1

Mobile

• Viewport meta tag present
• No mobile usability errors in Google Search Console