Wondering how to check if your website is SEO optimised? A systematic SEO audit covers four areas: technical foundations (how search engines access your site), on-page elements (how well individual pages are optimised), content quality (how useful and authoritative your content is), and off-page signals (the authority your site has earned from other websites). This guide walks through each area with the specific things to check and the tools to use — most of them free.
Technical SEO Checks
Technical SEO is the foundation. If search engines cannot crawl, render, or index your pages properly, all other SEO work is wasted.
Indexation — check that your important pages are indexed. Search site:yourdomain.com in Google to see how many pages are indexed. Then open Google Search Console, go to Pages (in the Index section), and check for pages marked "Discovered - currently not indexed" or "Crawled - currently not indexed." Pages that should be indexed but are not need investigation.
Robots.txt — verify your robots.txt file (at yourdomain.com/robots.txt) is not accidentally blocking important pages or your entire site from crawling. A common mistake is leaving a "Disallow: /" directive from a development environment in the production robots.txt.
XML sitemap — confirm you have an XML sitemap submitted to Google Search Console. It should include all important, canonical, indexable pages and exclude redirects, noindex pages, and canonicalised duplicates.
HTTPS — verify your site serves all pages over HTTPS (the padlock icon in the browser). HTTP is a confirmed negative signal. Use a tool like SSL Labs to check your SSL certificate configuration.
Page speed and Core Web Vitals — run your key pages through Google's PageSpeed Insights tool. Check your Core Web Vitals scores: Largest Contentful Paint (LCP) should be under 2.5 seconds, Cumulative Layout Shift (CLS) under 0.1, and Interaction to Next Paint (INP) under 200ms.
Mobile-friendliness — Google uses mobile-first indexing, meaning the mobile version of your site is what Google primarily crawls and indexes. Use Google's Mobile-Friendly Test or check the Mobile Usability report in Search Console for issues.
Canonical tags — ensure pages with duplicate or near-duplicate content have correct canonical tags pointing to the preferred URL. Read our canonical tags guide for a detailed explanation.
On-Page SEO Checks
On-page SEO covers the optimisation of individual page elements that help search engines understand what each page is about.
Title tags — every page should have a unique, descriptive title tag under 60 characters that includes the page's primary keyword near the beginning. Check for missing titles, duplicate titles, and titles that are too long or too short using Screaming Frog or our built-in tools.
Meta descriptions — while not a direct ranking factor, meta descriptions influence click-through rate. Every important page should have a unique meta description of 120–155 characters that summarises the page content and includes the primary keyword. Use our meta tag generator to write optimised meta descriptions.
H1 headings — each page should have exactly one H1 heading that clearly describes the page topic and includes the primary keyword. Pages without an H1 or with multiple H1s have a common on-page SEO issue.
Heading hierarchy — after the H1, content should use H2 for major sections and H3 for subsections. A logical heading structure helps both users and search engines understand content organisation.
Image alt text — all meaningful images should have descriptive alt text. Missing alt text is both an accessibility issue and a missed SEO opportunity for image search visibility.
URL structure — URLs should be short, descriptive, and include the target keyword where natural. Avoid dynamic parameters, excessive subdirectories, and non-descriptive slugs like /page?id=123.
Internal linking — every important page should be reachable from other pages on your site via contextual internal links. Orphan pages (pages with no internal links pointing to them) receive no PageRank and are harder for Google to discover and evaluate.
Content Quality Checks
Content quality is assessed by Google through E-E-A-T signals: Experience, Expertise, Authoritativeness, and Trustworthiness.
Depth and comprehensiveness — compare each important page to the top 3 competing pages for its target keyword. Does your content cover the topic as thoroughly? Does it answer the questions users have? Use our readability checker to assess how your content reads compared to industry standards.
Originality — avoid duplicate content (content copied from other sites or from your own pages on different URLs). Google's Panda algorithm targets thin and duplicate content. Every page should offer unique value beyond what exists elsewhere.
Keyword usage — check that your primary keyword appears in the title, first paragraph, at least one H2 heading, and naturally throughout the body. Use our keyword density checker to verify keyword presence without over-stuffing — aim for 1–2% density.
Content freshness — outdated content on time-sensitive topics (guides referencing old software versions, statistics from five years ago, advice that has since changed) needs refreshing. A content audit identifies which pages are stale.
Author authority — Google's quality rater guidelines specifically mention author expertise as a trust signal. Adding author bios with credentials, linking to author profiles, and including references to external authoritative sources builds E-E-A-T.
Off-Page and Authority Checks
Off-page SEO — primarily backlinks — determines how much authority search engines assign to your domain and individual pages.
Referring domains — check the number of unique domains linking to your site in Google Search Console (under Links) or a tool like Ahrefs/Moz. A growing number of referring domains over time indicates healthy link acquisition. A declining number may indicate link loss.
Link quality — not all backlinks help. A toxic backlink profile (many links from spam sites, link farms, or irrelevant low-quality sites) can harm rankings. Review your link profile for suspicious patterns. If you have received a manual action notice in Search Console for unnatural links, a disavow file may be necessary.
Brand mentions — search for your brand name in quotes on Google to find where you are mentioned online. Unlinked brand mentions are opportunities to earn backlinks by contacting the mentioning sites.
Local citations (for local businesses) — if you have a physical location, check that your Name, Address, and Phone number (NAP) are consistent across Google Business Profile, Bing Places, Yelp, and local directories.
Free SEO Audit Tools
A full SEO audit uses multiple tools. The essential free options:
- Google Search Console — the most important free SEO tool. Covers indexation, Core Web Vitals, mobile usability, manual actions, and link data. Set it up if you have not already.
- Google PageSpeed Insights — analyses page speed and Core Web Vitals for any URL.
- Screaming Frog SEO Spider — free for up to 500 URLs. Crawls your site and identifies missing titles, meta descriptions, broken links, duplicate content, and redirect chains.
- SearchRankTool checkers — our free keyword density checker, meta tag generator, SERP preview, and readability checker cover key on-page SEO elements.
- Ahrefs Webmaster Tools — free for site owners. Provides backlink data, crawl reports, and keyword rankings for your own site.
Prioritising Your Fixes
A full SEO audit typically uncovers more issues than can be fixed at once. Prioritise by impact and effort:
- Fix first (high impact, low effort): missing title tags, missing meta descriptions, broken internal links, pages blocked from indexing that should be indexed, missing alt text on key images.
- Fix soon (high impact, higher effort): page speed improvements, thin content on important pages, fixing duplicate content with canonicals, earning backlinks to key pages.
- Monitor and address over time: expanding content on pages ranking on page 2–3, improving internal linking structure, acquiring new backlinks through content marketing.
Re-audit quarterly to track progress and catch new issues introduced by site updates or content changes.
Frequently Asked Questions
How long does an SEO audit take?
A basic SEO audit of a small site (under 100 pages) using Google Search Console and Screaming Frog takes 2–4 hours. A comprehensive audit of a large site (thousands of pages) with full backlink analysis, content quality review, and technical deep-dive can take several days. For most small businesses, a focused audit of the top 20–30 most important pages is more actionable than an exhaustive audit of every page.
Can I do an SEO audit for free?
Yes. Google Search Console is free and provides the most authoritative data about your site's search performance. Screaming Frog's free tier (up to 500 URLs) covers technical on-page issues. Google PageSpeed Insights and the Mobile-Friendly Test are free. Our free tools at SearchRankTool cover keyword density, meta tags, and readability. A thorough manual audit using these free tools will identify the most important SEO issues.
What is the most important thing to check in an SEO audit?
Indexation is the most foundational check — if your important pages are not indexed, no other optimisation matters. After confirming proper indexation, page speed and Core Web Vitals are the most impactful technical signals to address, followed by on-page elements (titles, headings, content quality) and backlinks. Fix the technical foundation first, then build on it with content and link work.
How often should I audit my website's SEO?
Run a full technical audit quarterly. Audit new content (title tag, meta description, keyword usage, internal links) before or immediately after publishing. After major site changes (redesign, platform migration, URL restructure), run an immediate post-change audit to catch any technical issues introduced by the change.