A website audit is the most valuable thing a digital marketer can do for a new client — it gives you a baseline and a prioritised list of fixes. The catch is that no single tool finds everything. The best audits combine three or four tools that each catch different categories of issues. This is the stack I've used for the last five years across about a hundred client engagements.

Most beginners make the same mistake when they first run a website audit: they generate a 200-page Screaming Frog export, hand it to the client, and call it a day. That's not an audit. That's a data dump.

A real audit prioritises issues by impact, separates "broken" from "could be improved," and explains why each issue matters. To do that well you need a small set of tools that you understand deeply, not a big set you've barely used.

Free tools that are non-negotiable

These five are mandatory. If you don't use them, you can't claim to have audited a site.

Google Search Console

Free, run by Google. Search Console is the only tool that shows you exactly how Google's crawler sees your site. The Coverage report tells you which pages are indexed and which are excluded (and why). The Performance report shows real query and click data. The Core Web Vitals report shows speed issues directly tied to ranking signals.

If you don't have Search Console verified for the site you're auditing, your audit is incomplete. Get the client to add you as a user before you start.

Google PageSpeed Insights

PageSpeed Insights runs the same Lighthouse audit Google itself uses. It's the only authoritative source for Core Web Vitals data. Run it on your client's top 5-10 traffic-driving pages, not just the homepage. Mobile scores under 75 indicate problems.

The bonus: PageSpeed Insights includes an "Opportunities" section that gives you specific, actionable recommendations. Things like "Properly size images" with the exact files that need attention, or "Reduce unused JavaScript" with the bytes you'd save.

Lighthouse (in Chrome DevTools)

The desktop version of the same engine PageSpeed runs. Open Chrome DevTools, go to the Lighthouse tab, click "Analyze page load." You get the same Core Web Vitals data plus accessibility, SEO, and best-practices audits.

What's better than PageSpeed: you can run it on staging URLs, password-protected pages, and any URL you have access to. PageSpeed Insights only works on publicly indexable URLs.

Schema Markup Validator

Schema.org's official validator. Tests structured data on any URL. Critical because Google has been increasingly strict about structured data quality — bad markup gets your rich results dropped.

URL Inspection in Search Console

This one's a sub-feature of Search Console but deserves its own mention. The "URL Inspection" tool shows you exactly what Google sees when it renders a page. If your site uses client-side JavaScript rendering, this is how you verify Google can actually see the rendered content.

Digital marketer running a comprehensive website audit on a laptop
A complete audit usually takes 4-6 hours of focused work for a small site, and 2-3 days for a large enterprise site.

Some paid tools have free trials or limited free tiers worth checking before you decide to subscribe.

Screaming Frog SEO Spider

The single best site crawler. Free for up to 500 URLs; £199/year for unlimited. If you're auditing client sites professionally, the paid version pays for itself with the first audit.

Screaming Frog catches: broken links, redirect chains, missing meta tags, duplicate content, orphan pages, oversized images, and dozens of other issues. It's the desktop application I use most for technical SEO audits.

Ahrefs Site Audit

Part of an Ahrefs subscription (starting around $129/month). Cloud-based crawler with a polished UI and clear issue prioritisation. The free Webmaster Tools tier lets you crawl your own verified properties.

What it does better than Screaming Frog: prioritises issues automatically, integrates with the rest of the Ahrefs suite (backlinks, keywords, content) for a unified view, and emails you when new issues appear.

Semrush Site Audit

Similar to Ahrefs Site Audit. Often slightly more affordable. Stronger on competitor comparison features.

Sitebulb

Desktop crawler with a strong reputation among technical SEOs. Smaller user base than Screaming Frog but better at certain advanced analyses (JavaScript rendering, internationalisation).

Specialised tools for specific audit areas

Generic site auditors miss issues in specialised areas. These tools fill the gaps:

Accessibility audits

  • axe DevTools, free Chrome extension. The most respected accessibility checker.
  • WAVE by WebAIM. Free web-based accessibility checker. Visual indicators on the page itself.

Accessibility issues affect both SEO (Google notices) and UX (your users notice). Many sites have completely fixable accessibility problems they don't know about.

Schema and structured data

Mobile-friendliness

Image audits

  • ImageOptim (Mac, free) — desktop image compression.
  • Squoosh — Google's web-based image optimiser. Free, generous formats.
  • TinyPNG — bulk PNG/JPG/WebP compression. Free tier is plenty for most audits.

Internationalisation

For ad-hoc spot-checks during an audit, the free tools I built into this site cover several common needs:

A repeatable audit framework

The tools matter less than the framework. Here's the order I follow on every audit:

1. Verify ownership and access (10 minutes)

Get added to Search Console, GA4, the CMS, hosting panel, and analytics tools. Without these, your audit will miss critical context.

2. Crawl the site (1-2 hours depending on size)

Run Screaming Frog or Ahrefs Site Audit. Let it complete fully before drawing conclusions. Note the headline numbers: total URLs, indexable URLs, redirects, broken links, missing tags.

3. Search Console audit (1 hour)

Coverage report. Which pages are excluded? Why? Performance report; what queries does the site rank for? Where are the click-through rate gaps? Core Web Vitals — which URL groups have problems?

4. PageSpeed Insights on top pages (30 minutes)

Run on the 5-10 most important pages by traffic. Note the LCP, INP, CLS scores. Identify the pattern (are images the issue? JavaScript? render-blocking CSS?).

5. Manual content audit (1-3 hours)

Crawler tools can't tell you whether content is good. Open the top 20 pages by traffic and read them. Are they helpful? Are they out of date? Could a competitor easily improve on them?

6. Backlink audit (1 hour)

Use Ahrefs or Search Console's backlink data. Identify any spammy inbound links worth disavowing. Note the strongest natural links — these are your competitive moat.

7. Structured data audit (30 minutes)

Run Schema Markup Validator on the homepage, a product page, and a blog post. Check rich results test for any rich-result-eligible pages.

8. Prioritise findings (1 hour)

Bucket every issue into:

  • Must fix this week (broken sitewide functionality, security issues, indexing blockers)
  • Should fix this month (Core Web Vitals failures, missing meta tags on top pages, content gaps)
  • Could fix this quarter (style improvements, minor structured data gaps, cleanup tasks)

A list of 200 issues with no prioritisation is useless. A list of 20 prioritised issues is gold.

What good audit deliverables look like

Most clients can't read a Screaming Frog export. Translate your findings into something usable:

  • Executive summary; one page, three to five key findings, written for the client's CEO not their developer.
  • Prioritised issue list. Must/should/could format with effort estimates.
  • Specific recommendations per issue; not "fix slow pages" but "compress these 12 hero images using WebP, expected page-speed improvement: 0.4 seconds LCP."
  • Quick-win checklist — three to five things the client can do this week without involving a developer.
  • Long-term roadmap — six-month plan for the structural improvements.

A good audit deliverable is a 10-15 page PDF that a non-technical CMO can hand to their developer. Don't make the developer translate.

Anti-patterns to avoid

A few common audit mistakes:

  • Reporting every issue. Most "issues" found by crawlers are irrelevant. Filter ruthlessly.
  • Not testing on mobile. 70%+ of traffic is mobile. Audit mobile first, desktop second.
  • Ignoring competitors. A site can be technically perfect and still rank poorly because competitors are stronger. Always include competitive context.
  • Tool addiction. Don't recommend that the client buy six new tools. Recommend they use one well.
The point of an audit isn't to show the client how much you know. It's to give them a clear, prioritised path to better organic performance. The shorter your final report, the better job you've done filtering.

If you're auditing for your own site rather than a client's, the same framework applies, just be honest with yourself about which issues you're going to fix vs. Which you'll keep ignoring. Self-audits fail when the auditor is also the only person who has to do the fixing.

Final thoughts

Tools don't audit a site — auditors do. The most expensive software on this list is useless if you don't know what to look for. Start with the free tools, learn what good and bad look like, and only upgrade to paid tools when you find yourself doing the same manual checks over and over. The skill is in interpretation, not licence count.

Need help applying this to your own site? I'm Shani Maurya — a freelance web developer and digital marketer based in Delhi. If you'd like a hands-on audit or full implementation, get in touch — I usually reply within a few hours.