What is crawling in seo ? (crawling, indexing, ranking)

Wondering what is crawling in SEO? Imagine Google as a spider crawling the web to index pages. If your site isn’t crawlable, it won’t rank! Learn how search engine bots like Googlebot work, why crawling matters, and how to optimize your site for better rankings.
Liana Madova's avatar
Apr 02, 2025
What is crawling in seo ? (crawling, indexing, ranking)

If you want your website to rank well on search engines, you need to understand how crawling works.

Think of Google as a digital spider weaving its way through the web, scanning every corner of your site to discover and index its content.

But how does this process actually work? And more importantly, how can you ensure that Google finds and ranks your pages effectively? Let’s dive in and break it all down!

image of robot crawling websites

What is crawling in seo, and why does it matter?

Crawling is the essential first step before a page can appear in Google’s search results. It’s the process by which search engine bots—also called crawlers (automated programs that browse the web) or spiders (software agents that systematically explore websites)—discover, explore, and index new web pages to match user search intent.

Also known as spidering (the act of following links to find and catalog content), this process allows crawlers like Googlebot (Google’s web crawler) and Bingbot (Bing’s web crawler) to navigate your site and collect valuable information. They move through the web by following links between pages, automatically jumping from one piece of content to another.

common search engine crawlers

Think of Googlebot as an explorer in a massive library, flipping through books (web pages) and taking notes (indexing: the process of adding pages to a searchable database) to help users find the most relevant information. If your site isn’t crawlable, it’s like having a book that’s missing from the library catalog—no matter how valuable its content, no one will ever find it!

If you're setting up a new blog, ensuring proper crawling is essential. You can follow the simplest guide to adding a blog to your website to ensure everything is optimized from the start.Using a blogging platform optimized for SEO, like InBlog, ensures that your content is easily crawlable and indexed efficiently by search engines.

How do crawlers work?

processus of how crawlers work

To explore and index web pages, crawlers rely on multiple factors, including:

  • Links : Both backlinks (links from other websites that point to your site) and internal links (links within your site that connect different pages) help guide crawlers.

  • Content quality : The depth, relevance, and freshness of your site’s content impact how well it’s indexed.

Also, Writing a good meta description also plays a role—check out how to write a good meta description to craft the perfect snippet.

  • Domain name : A well-structured and trustworthy domain can aid crawling efficiency.For a better understanding of domain structures, you might want to explore Subdomain vs Subdirectory: which one is better for SEO.

  • XML sitemap : A file that lists all the pages of your website (an XML sitemap: a roadmap for search engines) to help them understand your site's structure and prioritize pages for crawling.

  • SEO elements : This includes meta-tags (snippets of text that describe a page’s content), canonical URLs(preferred versions of web pages to avoid duplicate content), and structured data that influence how your content is indexed.

    For more details on SEO optimization, read everything you need to know about blog SEO.

Since crawling happens before a site can be ranked in search results, optimizing your site for effective crawling is a critical step in achieving SEO success.

Crawl budget: Important factor for SEO

robot crawling sites

Crawl budget refers to the number of pages Googlebot is willing to crawl on your site within a given timeframe. If Googlebot wastes time on low-priority pages, it may not reach your most valuable content—hurting your rankings.

Several key factors influence crawl budget:

  • Site authority (a measure of your website’s credibility based on backlinks and trust signals) :   High-authority sites, like major news outlets, are crawled more frequently.

  • Page speed : Slow-loading pages slow down Googlebot, limiting how many pages get crawled.

  • Duplicate content : Confuses Google and wastes crawl resources.
    Example: An online store with the same product description across different color variants might see unnecessary crawling on redundant pages.Also, frequent changes to URLs can impact SEO and can contribute to duplicate content issues if not handled properly; learn more how frequent URL changes can negatively impact SEO.

Use Google Search Console (a free tool for monitoring and optimizing site performance) to analyze crawl stats and make sure Googlebot focuses on your most important pages.

How does crawling impact SEO?

Here’s the thing about crawlers: they’re just bots. They don’t have a built-in sense of what to crawl or ignore. They need directions.

Without clear instructions, these bots can end up wasting time crawling pages that don’t matter for SEO—like old subdomains, endless search URL variations, or tracking parameters. That’s a problem because it drains valuable crawl resources.

By guiding crawlers toward the right pages, you ensure they focus on SEO-relevant content. This keeps things efficient, helps avoid unnecessary status code errors, and makes your site look better to search engines.

If you're choosing a blogging platform, selecting the right one is crucial. Explore 15 best blogging platforms to find the best option for your needs.

What you should let search engines crawl:

  • Homepage

  • Product & service pages (including variations)

  • Landing pages (that work across different channels)

  • Blog articles

  • Resources & templates

  • Image & script URLs (including JavaScript & CSS)

What you shouldn’t let search engines crawl:

  • Pages with private information (business or user data)

  • Checkout pages

  • Login-protected URLs

  • Plugin or API URLs (not meant for content)

  • Temporary admin pages (like T&Cs for a one-time giveaway)

  • Duplicate content (if crawl budget is a concern)

  • Site search URLs (to avoid cluttering the index)

This tweet of Gary Illyes highlights the importance of blocking access to pages that don’t directly serve the purpose of indexing and SEO:

Tweet from Gary Illyes about blocking non-SEO pages from indexing

By managing what gets crawled, you optimize your website’s efficiency and SEO impact

Key factors for a good crawl experience

Want Google to crawl and index your site effectively? Here’s what you need to optimize:

1. Internal linking

Googlebot navigates your site like a tourist using a map—internal links guide it to important pages. A solid internal linking strategy ensures search engines find and prioritize key content.

Example: If your homepage links to a major product page, Google sees it as important. But if a page has no internal links (an orphan page, a page with no inbound links), it may never get crawled.

2. Sitemap & Robots.txt

  • XML Sitemaps (a file listing all your website’s pages) tell search engines which pages to crawl.

  • Robots.txt (a file that gives crawling instructions to bots) helps block unnecessary pages, like admin or duplicate content pages.

    processus of how webcrawler and robots.txt works

Quick fix: Submit your sitemap in Google Search Console to speed up indexing.

3. Canonical tags (avoid duplicate content issues)

If similar content appears on multiple URLs, canonical tags (HTML tags that specify the preferred version of a page) help prevent Google from splitting ranking power between duplicates.

Example: An e-commerce site selling the same product in different colors should use canonical tags to tell Google which URL to prioritize.

4. Optimized meta tags & structured data

  • Meta tags (HTML elements like title and description) give search engines a summary of your page.

  • Structured data (schema markup, a special code that helps search engines understand content) improves visibility in search results.

Example: A recipe site using schema markup can tell Google the exact ingredients and cooking time, increasing the chances of appearing in rich snippets (enhanced search results with extra details).

For blogging success, leveraging structured data can improve rankings. Check out blogging statistics : Key metrics you need to know for blog growth for insights on blog performance.

5. Fast & mobile-friendly site

Google prioritizes mobile-first indexing (ranking based on the mobile version of a site). If your site is slow or difficult to navigate on a phone, Googlebot may struggle to crawl it efficiently.

How to check if Google is crawling your site

  1. Google’s "site:" Command: Type site:yourwebsite.com in Google to see what’s indexed.

  2. Google Search Console: Check the “Coverage” report for crawling issues.

  3. SEO Tools: Use Ahrefs, SEMrush, or Screaming Frog to analyze crawl data.

What are the different types of crawling robots?

So, there are a few types of robots that "crawl" the web, and each one has its own job. Let me break it down for you in simpler terms, with some examples.

1. The indexing robot:
This is the robot that Google, as well as other search engines, uses. Its job is to crawl the web and gather information about websites so that Google can show the most relevant results when you search for something. Basically, it’s like a digital librarian organizing all the "books" (web pages) in the library so you can find what you’re looking for quickly.
For example, when you search for "best Italian restaurant in Paris" on Google, it’s this robot that has crawled websites to figure out which ones are most relevant to your search. The number of pages it crawls depends on the site's "health."

2. The diagnostic robot:
This robot is super useful if you run a website or work in SEO. It’s like a doctor checking up on a website to spot problems and suggest improvements. For example, it might tell you if some of your pages load too slowly or if you have broken links. In short, it gives you insights to help improve your own site.

3. The monitoring robot:
This one is mostly used by e-commerce sites. Let’s say you sell sneakers online, and you want to know what price your competitors are selling them for. This robot can regularly scan their sites to track their prices. It’s super useful for keeping an eye on market trends and adjusting your own prices accordingly. It’s like a little digital spy that keeps you updated in real-time!

What is the difference between crawling and indexing in seo?

Here’s something kind of strange about SEO that you might not know:
Google can index a page without crawling it.
Sounds weird, right? But it’s true. Let me break down the difference between the two.

Crawling and indexing are often confused in the SEO world, but they actually mean two very different things.

  • Crawling is when Googlebot (Google’s bot) checks out the content and code on a webpage to analyze it.

  • Indexing is when Google decides if that page is eligible to show up in search results.

Now, the tricky part is that crawling doesn’t always lead to indexing. Let me explain this with an example:

Think of Googlebot as a tour guide walking down a hallway with a bunch of closed doors.

  • If Googlebot is allowed to crawl a page (open the door), it can look inside and see the content (this is crawling).

  • Once inside, there might be a sign that says "You’re allowed to show people this room" (this is indexing—the page shows up in search results). But if there’s a sign saying "Don’t show anyone this room" (like a “noindex” meta tag), Googlebot won’t show it in the search results even though it can see the content.

But here’s where it gets interesting:

  • If Googlebot isn’t allowed to crawl a page (imagine a "Do not enter" sign on the door), it won’t go in and look at the content. So, it doesn’t know if the page has a “noindex” tag or not. But, it can still list the page in the index, even though it couldn’t check the content.

This is why blocking a page through robots.txt means it could still be indexed (even if there’s a “noindex” tag inside the page itself). If Google can’t crawl the page, it won’t see the “noindex” tag and will treat the page as indexable by default. But, since Google couldn’t analyze the page’s content, its ranking potential is reduced (since all ranking signals would come from off-page factors and domain authority).

You’ve probably seen a search result that says something like, "This page’s description is not available because of robots.txt." That’s exactly what’s happening.

Summary concerning difference between crawling and indexing :

Aspect

Crawling

Indexing

Definition

It's how search engines find new and updated web pages.

It's how search engines store and organize the pages they find.

Main purpose

Finding and grabbing web pages.

Analyzing and sorting content for search results.

Key tools

Uses bots (also called spiders or crawlers) to go through pages.

Builds an index (big database) to keep track of everything.

Goal

To discover new pages and gather content, making sure search engines know about all pages.

To make it easy for search engines to find and show relevant pages when you search.

Impact on SEO

Helps search engines find every page on your site, which affects visibility.

Makes sure the pages are stored and can show up in search results, affecting rankings.

Control options

You can guide crawlers with tools like robots.txt, sitemaps, and links within your site.

You can control indexing with things like canonical tags, meta tags, and good quality content.

Common tools

Google Search Console, Bing Webmaster Tools for tracking crawl issues.

Google Search Console, Ahrefs, SEMrush to check if pages are indexed.

Final thoughts:

Crawling is the first crucial step in helping your website get discovered and ranked by search engines. By understanding how Googlebot navigates your site, you can optimize your pages to ensure they’re crawled effectively and indexed correctly. From setting up internal links to using XML sitemaps, and from managing your crawl budget to blocking irrelevant pages, each step counts in boosting your SEO performance.

Leveraging SEO-friendly tools like InBlog for blogging and InPages for keyword research can help streamline your content strategy and improve search rankings.

Remember, crawling is just the beginning. Once Googlebot visits your site, it still needs to find the content relevant to users' queries and decide whether it's worth ranking. So, managing your website's crawl efficiency is not just about making sure Googlebot gets the information—it’s about giving it the right information to rank your pages higher in search results.

Also, for better blog engagement, consider embedding forms directly into your content—learn how in how to embed forms in your blog posts.By optimizing for efficient crawling, you set up your site for long-term SEO success!

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