SEO audit: where do you start?

An SEO audit is a lot more than a list of problems

A full SEO audit is not a static checklist. It is a systematic investigation of how your site performs against Google's ranking criteria, across four interdependent areas: technical, semantic, authority (link building) and competition. Each area turns up findings that affect the others. A technically flawless site with irrelevant content will never rank. Excellent content with no domain authority stays invisible. Here is where to start.

Phase 1: the technical audit (foundations)

The technical audit checks that your site can be crawled, indexed and served fast. This is the substructure. Without solid technical foundations, semantic work makes no sense.

Crawlability and indexing

• Robots.txt: Make sure it is not blocking Google from crawling your important pages. Check it in Google Search Console (GSC) under the crawl settings.
• XML sitemap: Build a sitemap that lists every page that matters and submit it in GSC.
• Indexing errors: The Pages report in GSC shows what is blocked, removed or returning errors. Deal with your revenue pages first.
• Canonicals: Check that every page carries a canonical tag, usually pointing at itself. Avoid canonical chains.
• Hreflang :

Performance and Core Web Vitals

Google states plainly that speed is a ranking factor. Use PageSpeed Insights or GTmetrix.

• Largest Contentful Paint (LCP): Time to render the main content. Target: < 2.5s
• First Input Delay (FID): Responsiveness to user interaction. Target: < 100ms
• Cumulative Layout Shift (CLS): Visual stability. Target: < 0.1

Quick wins: compress images, minify CSS and JavaScript, put a CDN in front, load scripts asynchronously.

Site architecture and URL structure

• URLs should be logical, readable and hierarchical (e.g. /blog/[category]/[article])
• Drop pointless parameters (?ref=123&utm_source=)
• Three to four clicks maximum from the homepage
• Avoid tangled structures: redirect chains and loops

Phase 2: the semantic audit (content and keywords)

Once the technical foundations hold, look at your semantic strategy. What content are you producing? For which keywords? How well does it answer what your audience is actually looking for?

Analysing the keywords you already have

• Open the Performance report in GSC. Which queries bring up your pages? What is your average position?
• Find the near-wins: keywords sitting in positions 5 to 15. Reworking the content can lift them into the top three.
• Weigh search volume against difficulty to spot the keywords worth chasing first.

Content gaps

Which relevant keywords do you not cover at all? Use Semrush, Ahrefs, or even a plain Google search operator:

• site:your-site.com [keyword] = how many of your pages cover that subject?
• [keyword] = what is the demand, and who owns the first ten results?

Build a matrix: high volume, low competition, high relevance. That is your priority list.

On-page analysis

For your 20 to 30 key pages, check:

• Title tag: Does it carry the keyword? 50 to 60 characters? Unique to that page?
• Meta description: 155 to 160 characters. Does it give a reason to click?
• Heading structure: One H1 per page, and the rest of the headings in a logical order
• Content: Around 800 words minimum to stand a chance. Keyword density in the 1 to 2% range.
• Internal links: Are your money pages linked from the homepage and from other relevant pages?

"On-page work accounts for roughly 30% of ranking. The other 70%? Domain authority and contextual content."

Phase 3: the authority audit (link building)

Google reads backlinks as votes of confidence. Two sites with equivalent content: the one with the better link profile ranks higher.

Auditing your current backlinks

• List your backlinks with Ahrefs, Semrush or Moz
• Judge quality: authority of the linking domain, topical relevance, anchor text
• Spot the quick wins: authoritative sites already mentioning your brand without linking. Ask for the link.

Auditing toxic backlinks

Too many poor-quality links (spam, low-grade directories, private blog networks) can weigh your site down. Google lets you disavow the worst of them in Search Console.

Competitor link analysis

• Who holds the top three for your target keywords?
• Where do their best links come from?
• Can you reach the same sources?

Phase 4: strategic competitor analysis

Do not optimise in a vacuum. Understand who you are up against.

Pick your SEO competitors

Your commercial competitors are not necessarily your search competitors. A small agency can own a set of very specific keywords ahead of far larger groups. Identify the sites that actually rank for your key queries.

Benchmarking

• Content volume: how much do they publish, and how often?
• Backlinks: how many, and of what quality?
• Keywords: what does each of them rank for?
• Structure: how do they organise the information?

Prioritising: what to fix first

You cannot do everything at once. This is the order I work in:

1. Critical technical errors (week 1): Blocked pages, missing indexation, severe Core Web Vitals failures
2. Semantic quick wins (weeks 2 to 3): Rework the pages already sitting in positions 5 to 15: low effort, high impact
3. Building authority (months 2 to 3): Targeted link building and pillar content
4. Content expansion (month 3 onwards): Cover the content gaps and build topical clusters

The free tools that are enough to start

• Google Search Console: Essential, free
• Google Analytics 4: Free, and the baseline measurement setup
• Google PageSpeed Insights: Free, with real-world field data
• Ubersuggest, free tier: Basic keyword data, capped
• MozBar (Chrome extension): Free, Page Authority at a glance
• Screaming Frog SEO Spider: Free up to 500 URLs, excellent for crawling

The audit is only the starting point

An SEO audit surfaces the problems and the openings. The impact comes from execution: fixing the technical errors, producing content that lasts, building domain authority. That runs over six to twelve months, not two weeks. See our full SEO services and our expert GA4 setup .