If you want to know why your site is not ranking, the best technical SEO audit tools give you an honest look under the hood, and the good news is that the most useful ones are free. These tools crawl your pages the way Google does, then hand you a plain list of what is broken: slow pages, missing tags, broken links, pages Google cannot see. You do not need to be a developer to run them or to read the results.
In this guide I will walk through the free tools I reach for first, what each one actually catches, and how to make sense of the report without drowning in jargon. If you want the bigger picture first, our plain-English guide to technical SEO is a good companion read.
What a technical SEO audit actually checks
Technical SEO is the plumbing of your website. It is not about your words or your keywords (that is on-page SEO). It is about whether search engines can find, read, and trust your pages. A good audit tool looks for things like:
- Crawlability: can Google reach your pages at all, or is something blocking them?
- Indexing: are your pages actually in Google's index, or invisible?
- Speed and Core Web Vitals: does the page load fast enough to keep visitors and rank well?
- Mobile friendliness: does it work on a phone, where most searches happen?
- Broken links and redirects: dead ends that frustrate people and waste Google's time.
- Missing tags: title tags, meta descriptions, headings, and alt text gaps.
The tools below each cover some of that. Used together, they give you a fuller picture than any single one.
Google Search Console: start here, always
If you run only one tool, run this one. Google Search Console is free, comes straight from Google, and shows you exactly how Google sees your site. Nothing else has that inside view.
What it catches that others cannot:
- Which pages are indexed and which are excluded (and why).
- Crawl errors, like pages returning a "not found" or server error.
- Which search terms are already bringing you clicks.
- Mobile usability and Core Web Vitals data from real visitors.
The Pages report is the first place to look. If pages you care about show as "not indexed," that is a direct signal something needs fixing. We have a full walkthrough on how to set up Google Search Console, and once you are in, our guide to fixing crawl errors covers the common culprits.
Tip: Search Console shows problems but not always the cause. Pair it with a crawler (below) that inspects each page in detail, and you will usually find the "why" behind an "excluded" page.
PageSpeed Insights and Core Web Vitals
Slow sites lose visitors and rankings. Google's free PageSpeed Insights tool grades any page on speed and the three Core Web Vitals: loading, interactivity, and visual stability. You paste in a URL and get a score plus a prioritized list of what is slowing you down (oversized images are the usual offender).
Do not obsess over hitting a perfect score. Focus on the "Opportunities" section, which lists the specific fixes that will move the needle most. Our guide to Core Web Vitals for small business sites explains what each metric means and how to improve it without touching code you do not understand.
Free site crawlers
A crawler visits every page on your site like a search engine would and reports back on tags, links, and structure all at once. This is where you catch site-wide patterns, like fifty pages missing a title tag, that a single-page tool would never surface.
Screaming Frog SEO Spider (free up to 500 URLs)
Screaming Frog is the industry standard, and the free version crawls up to 500 pages, which covers most small business sites completely. It flags missing or duplicate title tags, missing meta descriptions, broken links, redirect chains, and pages blocked from indexing. It looks intimidating on first open, but you can ignore most tabs and focus on the ones for page titles, meta descriptions, and response codes.
Ahrefs Webmaster Tools (free for site owners)
Ahrefs offers a free tier for verified site owners that runs a "Site Audit" and gives you a health score with a plain-language list of issues sorted by severity. It is friendlier than Screaming Frog for beginners and explains each problem in a sentence or two, which takes a lot of the guesswork out of your first audit.
The single-purpose checkers worth bookmarking
Some checks are quick one-offs. Keep these free tools handy for spot checks:
| Tool | What it checks |
|---|---|
| Google Rich Results Test | Whether your schema markup is valid and eligible for rich snippets |
| Google's mobile testing (in Search Console) | Whether pages work on phones, which is what Google indexes first |
| XML Sitemap validators | Whether your sitemap is formatted correctly and complete |
| Robots.txt testers | Whether your robots.txt file is accidentally blocking important pages |
| Redirect checkers | Whether your 301 redirects point where they should, in one hop |
These take seconds to run and catch the small, sneaky problems that silently keep pages out of search results.
How to read your audit results without panicking
Your first audit will probably surface dozens of "issues," and that is normal for every site. The trick is knowing which ones actually matter. Work in this order:
- Fix anything blocking indexing first. A page Google cannot see is worth zero, so start with crawl errors, accidental "noindex" tags, and robots.txt blocks.
- Then fix broken links and redirect chains. These waste crawl budget and frustrate visitors.
- Then address speed and mobile. Compress images and clean up anything flagged in Core Web Vitals.
- Finally, tidy the tags. Missing titles, duplicate meta descriptions, and empty alt text. Important, but rarely urgent.
Not every warning needs action. A "meta description too long" flag will not sink your rankings. If you are new to this, our SEO starter checklist and our roundup of common SEO mistakes help you tell the truly important fixes from the noise. And if you would rather not touch any of it yourself, doing your own SEO is absolutely learnable one step at a time.
Frequently asked questions
Are free SEO audit tools good enough for a small business?
Yes, for most small business sites the free tools are more than enough. Google Search Console, PageSpeed Insights, and a free crawler like Screaming Frog or Ahrefs Webmaster Tools will catch nearly every technical issue a typical site has. Paid tools mainly add scale and competitor data, which matter more for large sites and agencies than for a local business with a few dozen pages.
How often should I run a technical SEO audit?
A full audit once or twice a year is plenty for most small sites, plus a quick check whenever you redesign, migrate, or add a lot of new pages. Keep Google Search Console open more regularly, though, since it will alert you to new problems as they appear rather than making you go looking.
What is the difference between a technical audit and an SEO audit?
A technical audit focuses on the plumbing: crawling, indexing, speed, and site structure. A broader SEO audit also covers your content, keywords, and links pointing to your site. Technical is one leg of the stool. Our guide on on-page, off-page, and technical SEO breaks down how the three fit together.