How to Crawl a Website Online for Free and Find SEO Errors

Quick Answer

You can crawl a website online for free using Ahrefs Site Audit or Bing Webmaster Tools Site Scan. Both help website owners find technical SEO errors without installing desktop software. Choose a tool, verify your website, set crawl limits, and review the results. A successful crawl does not guarantee Google indexing.

Key Takeaways

Online website crawlers help you find issues before they harm site use or search visibility. The right tool depends on your website, access rights, and audit goals.

• Ahrefs Site Audit offers 5,000 monthly crawl credits per verified project under its documented free allowance.
• Bing Site Scan runs online and supports website, sitemap, and URL-list scans with site-specific limits.
• Screaming Frog offers 500 URLs per free crawl, but it requires desktop software.
• Online crawlers can find broken links, redirect issues, missing metadata, and some indexing restrictions.
• A link crawler may miss orphan pages, blocked URLs, and links created through JavaScript.
• Comparing crawler results with XML sitemaps helps reveal pages that need further discovery checks.
• Google crawling, indexing, and ranking are separate steps, so a clean audit cannot promise search visibility.

For most website owners, start with a free cloud-based audit. Use its findings to fix confirmed faults before checking search-engine indexing.

Choose the Best Online Website Crawler for Your Needs

Ahrefs Site Audit and Bing Site Scan are strong starting points for owners who want to crawl a website online. Both work through web-based tools. They also let users review technical problems without writing code or installing a desktop crawler.

The best choice depends on the job. A small business may only need a basic technical review. An SEO team may need detailed reports, repeated scans, and wider URL coverage.

Some tools inspect websites. Others inspect Google's view of a page or submit known URLs. Those are different jobs. Comparing them as if they were the same can lead to the wrong purchase or audit plan.

Free Website Crawler Comparison

The following table compares documented tool features as researched on October 23, 2026. Free limits may change. Credits and scanned URLs may also be counted in different ways.

The limits come from the Ahrefs free account documentation, Bing Site Scan documentation, and Screaming Frog SEO Spider product page. The other entries reflect their documented service scope.

If you own the website and want an online audit, try Ahrefs or Bing first. Choose Screaming Frog when you need desktop control or detailed exports. Use Search Console when Google's own view of a URL matters most.

Ahrefs Site Audit for Website Owners

Ahrefs Site Audit is a cloud-based tool for technical SEO checks. You can open reports in your browser. You do not need to build a crawler or keep a desktop program running.

The Ahrefs Webmaster Tools page describes its site audit features, including checks for more than 170 technical and on-page SEO issues. The documented free allowance is 5,000 crawl credits per month for each verified project, as of September 3, 2026.

That is a useful starting allowance, but it needs care. Crawl credits do not promise 5,000 distinct website pages. Repeated requests and crawl settings can affect how credits are used.

Ahrefs is a good fit when you want a broad technical report. It can help you review page errors, internal links, metadata, and other site signals. Check the project's settings before starting so the scan stays within your intended scope.

Bing Site Scan for an Online SEO Audit

Bing Site Scan offers another browser-based choice. It works within Bing Webmaster Tools and provides an on-demand technical scan.

The tool supports three crawl scopes: a website, an XML sitemap, or a URL list. You can also set crawl depth, speed, and other limits.

This is useful when you only want to check one section. For example, you may want to review a store's product pages without starting with its whole website.

Bing sets a monthly crawl quota for each site. There is no verified universal free page count in the supplied research. Check your account's available quota before making a plan around it.

Bing Site Scan is a sensible choice for owners who already use Bing Webmaster Tools. Its findings are technical audit evidence, not proof of what Googlebot has fetched.

When a Desktop Crawler Makes More Sense

Screaming Frog SEO Spider is not a browser-only tool. It must be installed on a supported computer. Its free version can crawl up to 500 URLs per crawl.

Desktop software may be more useful when you need close control over URL filters, crawl settings, and exported data. Screaming Frog also offers paid features, including JavaScript rendering.

Use a desktop crawler when an online account does not meet your needs. Do not assume that a browser tool is better merely because it requires less setup.

Crawl a Website Online in Seven Steps

A good website crawl starts with the right scope, not the biggest possible scan. Set the pages you want to check, confirm access, and decide which results you need.

You can use the following process in a suitable online site-audit tool. Exact menu names differ across products. This is a general workflow based on documented tool features, not a claim that a live audit was run for this article.

Step 1: Choose a Website You Can Crawl

Start with a website you own or have permission to audit. Verify it through the chosen tool if required.

Avoid assuming that every online crawler can scan any public website without approval. Site owners may limit automated access, and some tools require verified ownership.

Set the main website address carefully. Check whether the preferred address uses www, a subdomain, or a specific section.

Step 2: Define the Crawl Scope

Choose whether to scan the whole approved website or a smaller area. Set a sensible page limit and crawl depth.

A crawl depth of one follows links from the starting page. Greater depth lets the crawler explore links found on later pages.

The final number of discovered URLs depends on the website's links and the crawler's settings. A small limit can stop the scan before important pages are found.

Keep the scope narrow for your first test. Once the report looks sound, widen it if needed.

Step 3: Locate Your XML Sitemap

Check the site's XML sitemap before running the crawl. It may list important URLs that should be available to search engines.

Google's sitemap overview explains how sitemaps help discovery. They are especially useful for large, new, or complex websites.

A sitemap is not a full record of every existing page. It can leave out valid URLs or include pages that are no longer suitable for indexing.

Save the sitemap URL set for later comparison. It provides a second view of your site's pages.

Step 4: Start the Online Crawl

Open your audit project and select the scan settings. Confirm the starting address, allowed scope, crawl limit, and speed.

Then run the scan through the tool's interface. The crawler will request permitted pages and follow links it can discover under its settings.

Avoid using the fastest possible crawl speed without checking server needs. Heavy automated traffic can place extra load on a website.

The Google crawl-budget guidance discusses the value of clean URL sets and sound server responses. Not every small website needs advanced crawl-budget work. Basic access and useful internal links often deserve attention first.

Step 5: Review the Main Results

Open the crawl report and start with errors that may affect important pages. Look for failed requests, broken internal links, unexpected redirects, and crawler restrictions.

Check titles, descriptions, and canonical signals where the tool provides them. A canonical signal helps describe the preferred URL among similar pages.

Treat the report as evidence from that crawler. It may not show the same result Googlebot would see.

Step 6: Export and Compare Your URLs

Export the URL results if your tool and account allow it. Keep the HTTP status, final URL, crawl depth, discovery source, and reported issue with each record.

Compare the crawled URLs with the XML sitemap. Add an authorized CMS export if one is available.

This helps reveal possible gaps. A missing URL is a reason to investigate, not proof that a page has no internal links.

For a deeper URL inventory method, see how to crawl a website for all URLs.

Step 7: Fix Issues and Check Again

Fix confirmed faults in order of importance. Start with problems affecting key pages and paths that users need.

After a repair, rerun the relevant audit. Compare the new findings with your first report. Record the date, settings, and changes so the results are useful.

A technical issue disappearing from one crawler report is good evidence of a fix. It is not proof that Google has already processed the change.

Read Your Crawl Report and Fix the Most Useful Errors First

Start with errors that prevent access to important pages. Then review misleading redirects, indexing restrictions, duplicate URL patterns, and weaker metadata issues.

A report may show dozens of warnings. That does not mean each warning deserves the same priority. A broken main service page can matter more than several low-value metadata notices.

Crawl Error Decision Table

The table below shows common findings and the first useful checks. It is a diagnosis aid. Each row points to evidence you should inspect before changing the website.

The first action should match the actual problem. For example, a 404 may be correct for a page that was removed on purpose. Redirecting every missing page to the homepage can hide the real issue rather than solve it.

Broken Links and Server Errors

A broken internal link sends users toward a URL that does not provide the expected page. Check whether the linked address contains a typo or points to a removed page.

If the page moved, update the internal link to the correct destination. Use an appropriate redirect when old URLs still need to work.

A 5xx response needs a different review. It points toward a server-side failure. Examine logs, recent changes, and the time of the failed request. One successful reload does not rule out a problem that appears only sometimes.

For a more detailed fault-finding process, see how to test website crawlability and find errors.

Robots.txt, Noindex, and Canonical Signals

These controls answer different questions. Robots.txt affects whether a crawler may fetch a URL. Noindex tells supporting search engines not to include a page in their index once they can read that directive.

Google's robots.txt documentation makes this distinction clear. A robots.txt block is not a reliable way to keep a URL out of search results.

If a URL is blocked from crawling, Google may not be able to read its noindex directive. Review both settings before changing either one.

Canonical signals help search engines choose among similar URLs. They are not a guarantee that Google will select the declared address.

For online stores, filters and tracking parameters can create many URL variants. The site's guide to crawling query strings and URL parameters covers this problem in more detail.

Missing Metadata and Content

A crawler may flag missing page titles, descriptions, headings, or content. Use those results to find pages that need a closer look.

Not every missing field has the same effect. A missing title on a key page deserves review, but a crawler warning alone does not tell you how much search traffic is at risk.

Check the page's purpose and actual content. Make sure its title fits the topic and helps readers understand the page.

For JavaScript websites, inspect both the original HTML and rendered page. A simple crawler may miss text or links created after scripts run. A browser-rendering option may help, but it must still respect site access rules.

Compare Crawl Results with Your Sitemap to Find Missing Pages

Compare at least two URL sources when you want better discovery coverage. A link crawler follows paths it can reach. A sitemap declares URLs the site wants crawlers to know about.

The difference between these sets can reveal problems. It can also reflect crawl limits, filters, redirects, or JavaScript behavior.

A Worked Example with Three URLs

Imagine a small U.S. service business with a public website. The examples below are fictional and are not results from a live scan.

The website has three URLs listed in its sitemap. A permitted link crawl starts from the homepage and follows normal HTML links.

The services page needs further review, but the result does not prove it is an orphan page. The crawler may have stopped too early. The navigation link could also depend on JavaScript.

First, check whether other pages link to /services/. Next, review crawl depth, URL filters, and access restrictions. Then inspect rendered links if the site depends on scripts.

Only after checking those factors should you describe the page as a likely orphan. An orphan page has no discoverable internal links within the examined site scope, though other discovery sources may still expose it.

Build a Useful URL Coverage Record

A URL list becomes more useful when it shows how each address was found. Do not rely only on a total page count.

Keep the following details when the tool provides them:

• Record each URL and the source that revealed it.
• Save the crawl date and final HTTP response.
• Keep the final destination for redirected URLs.
• Record sitemap membership and crawl depth.
• Save reported canonical and indexing directives.
• Note the page or link that led to each URL.
• Mark whether JavaScript rendering was checked.
• Record the issue, next action, and follow-up result.

These details help you explain differences between crawl runs. A report with fewer pages may reflect changed settings rather than a drop in website health.

A sitemap-only URL is a review candidate. A crawler-only URL may point to a missing sitemap entry or a page that should not be listed there. Neither result proves an indexing problem on its own.

Know When Crawl Coverage Is Incomplete

A website crawler cannot promise complete URL discovery from one starting page. Private content, blocked paths, missing links, JavaScript behavior, and crawl limits can all leave gaps.

A stronger inventory can combine internal-link crawling, XML sitemaps, and an authorized export from the website's content system.

This matters most during a migration or large site audit. Missing a valuable service page or product section can affect the quality of the final review.

Understand What a Website Crawl Cannot Prove About Google

A successful website crawl does not prove Google has crawled or indexed the same URLs. Your SEO crawler makes its own requests. Googlebot operates through Google's separate crawling and indexing systems.

Google's How Search Works documentation separates crawling, indexing, and serving results. These are related stages, but each answers a different question.

Crawling retrieves page content. Indexing involves processing and storing information about pages. Search results are selected later, based on the query and other signals.

Technical Eligibility Does Not Guarantee Indexing

Google's technical requirements for search identify three core conditions for ordinary indexing eligibility. Googlebot must not be blocked, the page must return HTTP 200, and it must have indexable content.

These are starting conditions, not an indexing promise. Duplicate content, canonical selection, and other factors can still affect whether a page enters the index.

An SEO crawler may report that a URL returns HTTP 200. That only shows the response seen by the crawler. It cannot prove that Googlebot received the same response or indexed the page.

Use Google Search Console for Google-Specific Checks

Google Search Console provides information about Google's processing of URLs. Its URL Inspection tool can show indexed information and offer a live test for supported checks.

Use the indexed report and live test together. The indexed report may describe an earlier version of the page. The live test checks current conditions within the tool's scope.

The site's Google Search Console URL Inspection guide explains how to read results and choose fixes.

A successful live test does not guarantee inclusion in Google Search. If the page still does not appear, check the reported reason, duplication, canonical selection, and content suitability.

Website Crawlers and IndexNow Serve Different Jobs

A crawler discovers and inspects URLs. IndexNow sends notifications about known URL changes to participating search engines.

The official IndexNow FAQ explains that URL notification does not guarantee immediate crawling or indexing. Search engines retain control over their own processing.

IndexNowFast offers URL submission, index-related status checks, bulk workflows, and other services. Its public homepage describes those features, but they should not be presented as a full website crawling engine.

A sensible workflow is to discover URLs, repair site faults, and then use the right search-engine tools. The site's bulk Google indexing methods comparison explains how submission choices differ.

Google's recrawl request guidance also warns that requests may take days or weeks and do not guarantee indexing. Repeating a request for an unchanged page does not make Google process it faster.

Frequently Asked Questions About Crawling Websites Online

These questions cover the issues website owners often face after their first scan. They explain free access, crawl limits, missing pages, JavaScript support, and search indexing. Start by checking what your crawler actually tested. Then compare its results with the website's sitemap and any available search-engine reports. A missing page or reported warning needs a closer check before you change the site. The answers below help you choose that next check.

Can I Crawl a Website Online for Free?

Yes. Ahrefs Site Audit and Bing Site Scan offer online crawling features for eligible site owners. Both require suitable website or property access. Their free use has limits, so check the current account terms before starting.

For a small site, begin with your most valuable public pages. Check the available quota before choosing the scan size. A free account may be enough for an initial audit, even when it cannot cover every URL.

Which Website Crawler Works Without Installing Software?

Ahrefs Site Audit and Bing Site Scan work through online accounts. You can start and review scans in a browser. Screaming Frog SEO Spider is different because it requires desktop installation.

An online crawler suits owners who prefer a browser-based workflow. A desktop tool may offer more local control. Choose based on the checks you need, not just the setup method.

Can an Online Crawler Find Every Page on My Website?

Not reliably from one link crawl. It may miss pages with no reachable internal links, blocked content, and JavaScript-created navigation. Compare the results with sitemaps and other authorized URL sources for better coverage.

A page missing from the results may also fall outside the scan settings. Check the crawl depth, limits, filters, and starting URL before calling it an orphan page.

How Do I Find Broken Links on My Website?

Run a crawl and review broken-link or failed-response reports. Check which pages link to each affected URL. Then repair the link, restore the needed page, or direct users to a suitable replacement.

Focus first on links used by visitors to reach key pages. Keep the original URL, response code, and linking page in your records. Those details make later checks easier.

Why Does My Sitemap Show More Pages Than My Crawler?

Some pages may lack reachable internal links. Your crawler may also have stopped at a limit, excluded paths, or missed JavaScript links. Check the settings and individual URLs before treating them as orphan pages.

Review several missing URLs rather than judging the totals alone. A sitemap-only URL may still be accessible through a link that the scan did not follow. The difference is a clue, not a final diagnosis.

Can an Online SEO Crawler Check JavaScript Websites?

Some tools support JavaScript rendering, but support varies by product and plan. A basic HTML crawl may miss content built by scripts. Compare raw and rendered content when a report looks incomplete.

Look at the site's main navigation first. If important links appear only after scripts run, confirm that your chosen crawler can process them. Do not assume every plan has the same rendering features.

Is It Safe to Crawl Someone Else's Website?

Do not assume a public page gives unlimited permission for automated scanning. Follow applicable access rules, website terms, and crawl restrictions. Use tools within their permitted scope and avoid traffic that may disrupt the site.

For a client project, confirm the approved hostnames and scan limits first. A written scope helps prevent unwanted requests to private, test, or third-party systems.

Does a Clean Website Crawl Mean Google Will Index Every Page?

No. A clean crawl shows that the tool did not report certain faults under its settings. Google makes separate crawling and indexing decisions. Use Search Console to investigate Google's view of important URLs.

Check whether Google knows the preferred URL and whether it reports an indexing issue. Keep the search-engine evidence separate from the technical audit. A clean crawl is useful, but it is not proof of indexing or ranking.

Your First Online Crawl: Recommended Next Action

Start with a small, useful audit of a website you manage. Pick Ahrefs Site Audit or Bing Site Scan, verify your property, and choose an approved section to scan.

Focus first on core business pages. Check that users and crawlers can reach them, that links lead to the right destinations, and that no unintended restrictions block access.

Save the initial crawl results. Compare them with your XML sitemap and review missing URL candidates. Repair confirmed faults before running another scan.

Once the technical checks are complete, use Google Search Console to review important URLs. Keep that evidence separate from the crawler report. A healthy crawl and confirmed Google indexing are different outcomes.

If you later need to submit or check known URLs, review the available indexing workflows and their limits. Treat URL submission as a separate step, not a substitute for fixing the website.

This browser-first process gives you a practical starting point. It also creates a clear record of what was checked, which problems were found, and whether the repairs worked.