Click image to open full size
How Google Search Ranks Pages
PageRank, content quality, freshness, and E-E-A-T
Related Labs
Related Worksheets
Google Search ranks pages by trying to match a user's query with the most useful, trustworthy, and accessible information on the web. Early search engines relied heavily on keywords, but modern ranking combines hundreds of signals. A page can rank higher because other reputable pages link to it, because its content answers the query well, or because it works smoothly on phones. Understanding ranking helps students see how algorithms turn a huge web graph into an ordered list of results.
A simplified ranking engine first crawls pages, stores them in an index, and then scores possible results when a query is entered. Link analysis such as PageRank treats links like votes, but it also weighs votes from important pages more strongly. Modern systems add content quality, freshness, location, page experience, mobile-first indexing, and E-E-A-T signals related to experience, expertise, authoritativeness, and trust. SEO is half science and half art because technical improvements can be measured, while user intent, helpful writing, and trust signals require judgment.
Key Facts
- Search ranking has three broad stages: crawl pages, index content, then rank results for a query.
- A simplified PageRank model is PR(A) = (1 - d) / N + d Σ(PR(B) / L(B)), where B are pages linking to A.
- In PageRank, a link from a highly trusted page usually counts more than a link from an unknown page.
- Relevance scoring often uses term frequency ideas such as TF = number of times a term appears in a page.
- Freshness matters more for time-sensitive topics like news, weather, prices, and recent technology.
- Mobile-first indexing means Google primarily evaluates the mobile version of a page for indexing and ranking.
Vocabulary
- Crawler
- A crawler is a program that follows links across the web to discover pages and collect their content.
- Index
- An index is a large searchable database that stores information about pages so results can be found quickly.
- PageRank
- PageRank is a link analysis algorithm that estimates a page's importance based on the quantity and quality of links pointing to it.
- E-E-A-T
- E-E-A-T stands for experience, expertise, authoritativeness, and trust, which are quality concepts used to evaluate whether content is reliable and helpful.
- SEO
- Search engine optimization is the practice of improving a site so search engines and users can better understand, access, and trust it.
Common Mistakes to Avoid
- Thinking keyword stuffing improves ranking, because repeating a phrase unnaturally can make content less helpful and may be treated as spam.
- Assuming all backlinks are equal, because links from reputable and relevant pages usually carry more value than links from low-quality or unrelated pages.
- Ignoring mobile usability, because mobile-first indexing means a slow or broken mobile page can harm how the page is evaluated.
- Believing Google uses one simple score, because modern ranking combines many signals and the importance of each signal changes with the query and context.
Practice Questions
- 1 A page has 12 backlinks. Four links come from strong pages worth 8 points each, and eight links come from weak pages worth 1 point each. Using this simplified model, what is the page's total link score?
- 2 A document has 900 words and the term 'climate' appears 18 times. Compute the term frequency as appearances per word, TF = 18 / 900, and express it as a decimal and a percent.
- 3 Two pages answer the same query. Page A has many exact keywords but is outdated, slow on mobile, and has no sources. Page B uses fewer exact keywords but is current, fast, written by an expert, and cited by reputable sites. Explain which page a modern search engine is more likely to prefer and why.