Technical SEO Audit: How to Check Crawlability, Indexability, and Site Health

A technical SEO audit is not a hunt for the largest possible number of warnings. It is a structured review of whether search engines can reach the right pages, understand which versions matter, and move through the site without unnecessary friction.

The useful question is not “How many SEO issues does this site have?” It is “Which technical conditions are preventing important pages from being discovered, understood, indexed, or maintained efficiently?”

This guide explains how to run a technical SEO audit in that order.

1. Define which pages matter

Before crawling anything, identify the page types the business actually depends on.

For a service site, that might include the homepage, core service pages, location pages, pricing pages, and major guides. For ecommerce, the priority set may include category pages, product pages, high-value collections, and supporting content.

This matters because the same technical signal can have very different consequences depending on where it appears. A broken internal link in an old blog post is not equivalent to a broken link in the primary navigation. A noindex directive on a filtered URL may be intentional; the same directive on a major landing page can be critical.

Create a simple inventory of important page types before evaluating severity.

2. Check crawlability before indexability

Crawlability answers a basic question: can a crawler request and move through the pages you want it to find?

Start with:

• robots.txt rules
• internal links
• XML sitemaps
• redirects
• HTTP status codes
• JavaScript-dependent navigation
• URL patterns that generate large numbers of low-value pages

Important pages should normally have a clear internal path from other useful pages.

Look for important URLs that are isolated, linked only from obscure pages, or accessible only after an interaction a crawler may not reproduce reliably. Also look for the opposite problem: crawl paths that generate endless combinations of parameters, filters, calendars, searches, or faceted navigation.

The goal is not to make every URL crawlable. It is to make the right URLs easy to discover while preventing low-value URL spaces from creating unnecessary crawl complexity.

For a more detailed list of checks, use the 30-point technical SEO audit checklist.

3. Separate “can be crawled” from “should be indexed”

Crawlability and indexability are related, but they are not the same.

A URL can return a normal 200 response and still be excluded from indexing because of a noindex directive, canonical signal, authentication requirement, duplicate-content relationship, or another indexing decision.

During the audit, check important pages for:

• meta robots directives
• X-Robots-Tag headers
• canonical targets
• duplicate or near-duplicate versions
• redirect targets
• status codes
• conflicting signals between HTML, headers, and sitemaps

The main objective is consistency. If a URL is meant to rank, the surrounding signals should reinforce that choice. It should not be listed in the sitemap while pointing its canonical elsewhere, or be internally linked as a primary page while also carrying noindex.

These conflicts often matter more than isolated warnings because they make the site’s intended structure harder to interpret.

4. Review canonicalization as a decision system

Canonical tags are easy to check mechanically and easy to misunderstand.

A canonical is a signal about which URL should represent a group of similar or duplicate pages. During an audit, ask:

1. Does the canonical resolve to a valid URL?
2. Is the destination indexable?
3. Is it the page the site actually treats as primary?
4. Do internal links mostly point to that preferred version?
5. Is the canonical consistent with redirects and sitemap inclusion?

For ecommerce sites, this becomes especially important when filters, sorting parameters, tracking parameters, product variants, and pagination create multiple routes to similar content.

Do not “fix” every non-self-referencing canonical automatically. Some are intentional. The audit should identify contradictions and questionable consolidation, not erase legitimate canonical strategies.

5. Follow redirects from source to destination

Redirects are normal. Redirect chains are usually a maintenance problem.

A common pattern develops over time:

Old URL → replacement URL → new category URL → final URL

Users may still reach the destination, but every extra hop makes the path more complicated and increases the chance that old internal links remain embedded across templates or content.

Inspect both the redirect and where the redirecting URL is still referenced. If an internal link points to URL A and A redirects to B, updating the internal link directly to B is usually cleaner than relying indefinitely on the redirect.

Also distinguish between permanent moves, temporary moves, deleted content, and URLs that should remain genuine 404s. Redirecting every removed page to the homepage does not create a meaningful replacement.

6. Audit internal links as site architecture

Internal links are not just a broken-link check. They describe the hierarchy of the site.

For important pages, review:

• number and quality of internal links
• anchor text
• depth from major navigation paths
• links from related pages
• links from outdated URLs
• orphaned or nearly orphaned pages

A technically valid page can still be difficult to discover if almost nothing links to it. Conversely, a low-value page linked from every template can receive disproportionate crawl attention.

For repairs involving dead or redirected URLs, see How to Fix Broken Links for SEO.

7. Check templates, not just individual pages

On medium and large sites, technical SEO problems are frequently template problems.

A single template mistake can affect hundreds or thousands of URLs: duplicated title patterns, incorrect canonical logic, internal links pointing to outdated paths, or parameterized URLs created by navigation.

When the same issue appears repeatedly, do not create hundreds of separate tasks. Identify the shared source.

If every product page has the same canonical error, the actionable finding is not “fix every canonical.” It is “correct the product template’s canonical logic and verify the affected set afterward.”

That distinction turns an audit into an implementation plan.

8. Verify JavaScript-dependent content

JavaScript is not automatically an SEO problem. The question is whether important content, links, metadata, and navigation are reliably available in the rendered experience.

Compare raw HTML and rendered output when a page depends heavily on client-side code. Pay particular attention to links inserted only after interaction, metadata changed after initial load, content fetched asynchronously, navigation that requires clicks, and routes that return thin HTML shells.

Do not recommend a site-wide framework migration simply because JavaScript exists. The audit should identify a specific discoverability or rendering problem before proposing a technical remedy.

9. Prioritize by impact, scope, confidence, and effort

Once the evidence is collected, resist the temptation to order findings by warning count.

Ask four questions:

Impact: What important page or process does the issue affect?

Scope: Is it one URL, one template, or the entire site?

Confidence: Do you have evidence that the issue is real and that the proposed repair addresses the cause?

Effort: Is the repair a link update, a template change, a routing change, or a larger engineering project?

A sitewide indexing conflict on important pages can deserve attention before hundreds of cosmetic metadata warnings.

For a fuller prioritization framework, read How to Prioritize SEO Issues After an Audit.

10. Turn findings into verifiable repairs

A technical SEO audit is useful only if someone can act on it.

Each important finding should include:

• the affected URL or pattern
• the evidence
• why it matters
• the likely root cause
• the recommended change
• who owns the change
• how to verify it after implementation

Avoid vague recommendations such as “improve crawlability” or “fix technical SEO.”

A better recommendation is specific: “Update the category template so product links point directly to the final 200-status URLs instead of redirecting through the discontinued path, then recrawl the category set to confirm the redirects are no longer internally linked.”

If you are packaging the work for a team, the SEO audit report guide explains how to structure the evidence and handoff.

11. Recrawl after fixes

Verification is part of the audit process.

After changes go live, recrawl the affected area and confirm that broken links resolve correctly, redirect chains are shortened, intended pages are indexable, canonical targets are valid, internal links point to preferred URLs, and template-level problems are gone across the affected set.

A ticket being marked “done” does not prove the technical condition changed.

The cleanest workflow is evidence → repair → recrawl → verification.

Where a website health scanner fits

A crawler can speed up evidence gathering, but it should not replace judgment.

FixList is a read-only website health tool. Its Standard 150 scan checks up to 150 pages and prioritizes what to fix first. It does not change a site automatically.

That makes it useful for building an initial technical picture: identify recurring issues, see which page groups are affected, and then decide which findings deserve action.

The important part is what happens after the scan. Technical SEO improves when findings are translated into specific repairs, assigned to the right owner, and verified once implemented.

Final takeaway

A good technical SEO audit is not a spreadsheet of warnings.

It is a map of how the site exposes important pages to crawlers, how it signals which URLs should be indexed, where those signals conflict, and which repairs will remove the most meaningful friction.

Start with crawlability. Separate it from indexability. Check canonical and redirect logic. Review internal links as architecture. Look for template-level causes. Prioritize by impact and scope. Then verify the repairs with a fresh crawl.

That process produces something much more valuable than an issue count: a technical SEO work plan that a team can actually execute.

FixList checks up to 150 pages and turns what it finds into a prioritized, plain-English list of what to fix first.