An SEO audit is a thorough analysis of everything that affects how well your website performs in search engine results. It looks at your technical setup, your on-page content, your backlink profile, your site speed, and dozens of other factors that determine whether Google decides to rank your pages or ignore them.
Most websites have SEO problems they are completely unaware of. Broken links, missing meta tags, slow load times, duplicate content, pages blocked from indexing — any one of these issues can quietly cost you traffic every single day. An audit surfaces all of them so you know exactly what needs fixing and in what order.
The good news is that you do not need expensive software to run a comprehensive SEO audit. This guide walks you through every major audit area step by step using free tools available right here on MerkSEO. Whether you are auditing your own site or a client's, follow this checklist and you will have a complete picture of your SEO health by the time you are done.
Meta data is the first thing search engines read when they discover your pages. Your title tags and meta descriptions directly influence both your rankings and your click-through rate in search results. Missing, duplicate, or poorly written meta data is one of the most common and impactful SEO problems found on any website.
Start by running your most important pages through the Meta Tags Analyzer to see exactly how your title tags, meta descriptions, and keywords appear to search engines. Check for the following on every key page:
If you need to create or rebuild your meta tags from scratch, use the Meta Tag Generator to produce correctly formatted meta tags for any page in seconds. Getting your meta data right is one of the fastest and most impactful on-page SEO improvements you can make.
Once your meta data is in order, the next step is making sure your page content is properly optimized for the keywords you want to rank for. Keyword usage that is too thin signals to Google that your content lacks depth. Keyword usage that is too aggressive looks spammy and can actively hurt your rankings.
Use the Keyword Density Checker to analyze any page and see which keywords appear most frequently and at what density. A healthy keyword density for your primary term is generally between 1 and 3 percent. Anything above that starts to look like keyword stuffing.
For a deeper look at how your content reads, run it through the Article Density Checker to see a full breakdown of word and phrase frequency. This is particularly useful for long-form content where you want to make sure your topic coverage is thorough and well-distributed.
If you are not yet sure which keywords to target, the Keywords Suggestion Tool and the Long Tail Keyword Suggestion tool will generate a list of relevant keyword ideas based on your seed topic. Long-tail keywords are especially valuable for newer sites because they have lower competition and higher conversion intent.
Before you can improve your rankings you need to know where you currently stand. Many website owners skip this step and have no baseline to measure progress against. Knowing your starting positions also helps you prioritise which keywords need the most attention.
Use the Keyword Position Checker to see exactly where your pages rank for your target keywords across Google. Enter your domain and the keywords you are targeting and you will get an instant snapshot of your current search positions. Run this check at the start of your audit and repeat it monthly to track your progress over time.
Page speed is a confirmed Google ranking factor and one of the most commonly neglected areas of technical SEO. A page that takes more than three seconds to load loses more than half its visitors before they even see your content. Slow pages also receive lower rankings, particularly on mobile where Google applies mobile-first indexing.
Run every key page on your site through the Page Speed Checker to get an instant performance score and identify the specific issues slowing your pages down. For a more detailed breakdown aligned with Google's official scoring, use the PageSpeed Insights Checker which pulls data directly from Google's PageSpeed API.
Common speed issues to look for and fix include:
Backlinks — links from other websites pointing to yours — remain one of the strongest ranking signals in Google's algorithm. The quality, quantity, and relevance of sites linking to you directly influence how much authority Google assigns to your domain. A weak backlink profile is one of the most common reasons a site fails to rank despite having good content.
Use the Backlink Checker to see which sites are currently linking to your domain. As you review your backlinks look for the following:
You can also check your overall domain authority score using the Domain Authority Checker and the MozRank Checker. These scores give you a useful benchmark for comparing your domain strength against competitors and tracking improvement over time.
Broken links — pages on your site that return a 404 error — damage your SEO in two ways. They create a poor user experience that increases bounce rate, and they waste crawl budget by leading search engine bots to dead ends. Every broken internal link also breaks the flow of link equity through your site.
Use the Broken Links Finder to scan any page for broken links. Work through your most important pages first — your homepage, your top-traffic pages, and your cornerstone content. Fix broken internal links by updating the destination URL. For broken external links, either remove the link or replace it with a working alternative.
For a broader picture of all links on any given page — internal and external — the Link Analyzer gives you a complete breakdown including link type, anchor text, and follow status.
A page that is not indexed by Google simply does not exist in search results. Indexing issues are surprisingly common and can be caused by misconfigured robots.txt files, noindex tags applied by mistake, or pages being blocked from crawling by your CMS settings. The first thing to check is whether your important pages are actually being indexed.
Use the Google Index Checker to verify whether specific URLs have been indexed. If key pages are missing from Google's index, investigate why. Common causes include:
Review and update your robots.txt file using the Robots.txt Generator to make sure you are not accidentally blocking important content. And if your site does not yet have an XML sitemap, create one immediately using the XML Sitemap Generator and submit it to Google Search Console. A sitemap tells Google exactly which pages exist on your site and helps them get indexed faster.
Your domain itself carries SEO signals that are easy to overlook. Domain age, hosting reliability, security certificates, and blacklist status all influence how Google perceives your site's trustworthiness.
Work through the following domain health checks as part of your audit:
Google's quality algorithms increasingly assess whether your content is genuinely useful to human readers. Thin content, poor readability, and low word counts are all negative signals. Content that is hard to read tends to have high bounce rates, which further signals to Google that the page is not satisfying user intent.
Use the Readability Checker to score your content against established readability formulas. Aim for a reading level appropriate to your target audience — most general web content performs best at around a 7th to 9th grade reading level, which is clear and accessible without being condescending.
The Word Counter can help you gauge content depth. While there is no magic word count for SEO, comprehensive content on competitive topics generally performs better when it covers the subject thoroughly — typically 1,500 words or more for pillar content.
If you are concerned about duplicate content either on your site or copied from elsewhere, run your pages through the Plagiarism Checker. Duplicate content can cause Google to demote or ignore affected pages, and in some cases to deindex them entirely.
The final step in your audit is to view your pages the way search engine crawlers actually see them — stripped of styling, JavaScript rendering, and visual elements. What appears beautiful in a browser may look completely different to a crawler, and understanding that gap is crucial for identifying hidden indexing issues.
Use the Search Engine Spider Simulator to see exactly what Googlebot sees when it visits any of your pages. Check that your most important content — your headings, body text, and links — are all visible to the crawler. If key content only appears after JavaScript execution it may not be getting indexed at all.
While you are at it, use the Code to Text Ratio Checker to see the balance between HTML code and actual readable content on any page. A ratio that is heavily weighted toward code and light on text suggests your page may not have enough substantive content for search engines to properly evaluate.
Once you have worked through all ten steps you will have a detailed picture of your site's current SEO health. The next step is prioritisation. Not every issue is equally urgent, so focus your effort in this order:
SEO is not a one-time task. Run a full audit every three to six months, and check individual areas more frequently as you make changes to your site. The websites that maintain strong rankings are the ones that treat their SEO as an ongoing process rather than a project with a finish line.
All of the tools referenced in this guide are completely free to use at MerkSEO.com. No sign-ups, no trials, and no paid tiers — just practical SEO tools you can use right now to find and fix the issues holding your website back.
Start with the Meta Tags Analyzer and the Page Speed Checker — two of the quickest audits you can run — and work your way through the checklist from there. You will be surprised what you find.