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What is PageRank? Understanding the Difference Between Google PageRank and Page Authority

what is pagerank

PageRank (Google PageRank) was once an official metric provided by Google to assess the quality of web pages. Known for its intuitive and straightforward SEO evaluation, PageRank gained significant attention.

However, due to rampant practices like buying backlinks and generating worthless link farms, warnings were frequently issued at Google Search Central, leading to the privatization of PageRank data. Subsequently, metrics such as Moz’s Page Authority (PA) and Domain Authority (DA) emerged as alternatives.

I will explain PageRank. This explanation is designed to be easily understood, even for SEO beginners, and covers how PageRank works and the history leading up to its discontinuation. I have also compiled information about the metrics that are used as alternatives to PageRank.

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PageRank Explained 

Initially, Google PageRank was a publicly visible score, allowing anyone to view a website’s rank. However, starting in 2013, PageRank scores were no longer public. In its absence, alternative metrics became prominent

  • Page Authority (PA)
  • URL Rating (UR)
  • Trust Flow (TF) / Citation Flow (CF)

Mechanism of PageRank 

PageRank assigned a score from 0 to 10 to web pages, indicating the quality and quantity of backlinks. A higher score suggested a website had many high-quality backlinks.

How to Calculating PageRank

The PageRank score is calculated based on the quantity and quality of backlinks a webpage has.

Related Article: What Are Backlinks?

According to a research paper by Larry Page and Sergey Brin, co-founders of Google, at Stanford University, PageRank is calculated as follows.

Assume page A has pages T1 through Tn pointing to it (i.e., citations). Let d be a damping factor that can be set between 0 and 1, typically set to 0.85. The function C(A) is defined as the number of links going out of page A. The PageRank of A is given as

PR(A) = (1-d) + d (PR(T1)/C(T1) + … + PR(Tn)/C(Tn))

Citation: The Anatomy of a Search Engine

This formula implies that the PageRank of a web page is determined by;

  • The increase in received value with each additional backlink.
  • Fluctuations in the received value based on the PageRank of the linking page.
  • The distribution of the received value according to the number of outbound links on the linking page.

Google interprets backlinks as citations, valuing pages with more backlinks as credible content. The quality of the backlink is judged higher if it comes from a website with a high PageRank, thus passing on a portion of its value.

Background of PageRank Discontinuation 

PageRank was introduced in 1998 and integrated into Google’s search engine algorithm. After about 15 years, between 2013 and 2016, Google phased out the public display of PageRank scores. 

However, it’s crucial to note that this discontinuation only refers to the public visibility of PageRank, not its removal from the search algorithm.

Excessive Focus on PageRank and Backlink Strategies

PageRank, being an indicator based on backlinks, garnered significant attention from website operators. Around 2005, the concept of ‘link juice’ became popular in the SEO industry.

Related Articls: What is Link Juice?

This led to the proliferation of the belief that backlinks were crucial for SEO, eventually turning into a business practice, where the following actions became prevalent.

-Selling backlinks for money

-Increase in link directories, which are considered to have low value as content

Such SEO strategies, overly focused on PageRank and link juice, diminished the usability of search engines. Google, recognizing this issue, implemented measures to penalize websites that accumulated low-quality backlinks in large numbers, leading to the discontinuation of public PageRank.

The Ongoing Relevance of PageRank 

Although PageRank became non-public post-2013, backlinks continue to be a vital element of search algorithms. As a result, strategies for acquiring natural and high-quality backlinks still play a significant role in SEO external measures today.

Related Article: What is Off-Page SEO?

For instance, suppose a company operates a media outlet reviewing frozen food products. They might propose an interview feature with a major food manufacturer. Upon conducting the interview and publishing the article, the company could negotiate to obtain backlinks from the manufacturer’s corporate website.

For backlinks to be effective, they should meet the following criteria

  • Relevant to the theme.
  • From an authoritative source.
  • Generated organically.

In this case, the food manufacturer’s corporate website is highly relevant to the theme of the frozen food review site and, being a direct provider of food products, holds significant authority in the sector. Hence, this scenario can yield effective backlink strategies.

Alternatives to PageRank

With PageRank no longer publicly accessible, globally recognized metrics for evaluating SEO have gained attention.

Research Firm | Metric Name | Measurement Target

  • Moz Page Authority (PA) the number and quality of backlinks and the number of ranking keywords.
  • Ahref URL Rating (UR) the number and quality of backlinks.
  • Majestic Trust Flow (TR) the quality of backlinks.
  • Majestic Citation Flow (CR) the number of backlinks.

These metrics, although they differ in precise calculation methods, score web pages based on backlinks and are widely used as a standard for SEO evaluation.

Related Article: What is SEO Evaluation?

Page Authority (PA) 

Page Authority (PA) is an SEO evaluation metric that indicates the authority of a page. It is a concept promoted by the major American SEO company, MOZ, and is calculated based on the following factors:

  • The number and quality of backlinks.
  • The number of keywords for which the page ranks in the top 100 of Google search results.

Additionally, Moz offers a metric for evaluating the entire website, known as Domain Authority (DA).

Both DA and PA are accessible through Moz’s SEO tools, available for free checks. For example, scores might be displayed as follows.

  • DA: 91
  • PA: 65

These figures are on a scale from 0 to 100, where a score closer to 100 signifies a higher evaluation. While DA and PA are different from PageRank in their calculation methods, they serve as a benchmark for SEO performance globally.

Related Article: What are Moz’s SEO Tools? Explaining How to Implement Effective SEO Strategies with Moz.

URL Rating (UR)

URL Rating (UR), measured by Ahrefs, is a metric indicating the value and popularity of a page. It is calculated based on the number and quality of backlinks.

Ahrefs also provides a whole-site metric known as Domain Rating (DR). Ahrefs describes the calculation of DR as below.

“How is Domain Rating Calculated?

Domain Rating is calculated in a manner similar to PageRank.

Citation: What is Ahrefs’ Domain Rating? Explaining the Basics of This Metric | Ahrefs Blog – Delivering Useful SEO Information | SEO Backlink Analysis & Competitor Research Tool

This means that DR and UR are metrics that are most similar to PageRank.

Citation: Ahrefs

Both DR and UR can be researched using Ahrefs’ paid tools. For example, in an illustrative case, the values might be as follows.

  • DR: 62
  • UR: 40

Related Article: What is Ahrefs? A Comprehensive Guide from How to Use It to Key Considerations.

Trust Flow (TR) / Citation Flow (CR) 

Trust Flow (TR) and Citation Flow (CR), proposed by Majestic, are SEO metrics where TR scores the quality of backlinks and CR scores the quantity. These two metrics work in tandem, and their balance is crucial for a holistic SEO evaluation.

Frequently Asked Questions about PageRank 

Here are some common questions about PageRank summarized in an FAQ format

Q: What is the history and origin of PageRank? 

A: PageRank first appeared in 1998, with its patent filed on September 1 of that year. It was then incorporated into Google’s search engine algorithm and made public around 2000. However, the exploitation of PageRank’s mechanics by black-hat SEO tactics led Google to cease its public disclosure around 2013, and the patent for PageRank was allowed to expire in 2018 without renewal.

Q: Who created PageRank? 

A: PageRank was developed by Google co-founders Larry Page and Sergey Brin. The concept of PageRank was introduced in their academic paper ‘The Anatomy of a Search Engine’ at Stanford University.

Q: Has PageRank been discontinued? 

A: Yes, Google announced the discontinuation of PageRank in 2013. However, this means that PageRank is no longer publicly displayed.

PageRank is calculated based on the quantity and quality of backlinks. As of 2024, while not as influential as before, backlinks still have a certain SEO effect. The backlink element has not been removed from the Google search engine algorithm; rather, it is the PageRank metric itself that has been discontinued.

Q: How can PageRank be checked? 

A: As of 2024, there is no way to check PageRank because it’s no longer publicly available. However, similar metrics like Domain Authority (DA), Page Authority (PA), Domain Rating (DR), URL Rating (UR), Trust Flow (TR), and Citation Flow (CR) are used as indicators in SEO evaluations.

Q: How can PageRank be increased? 

A: Since the PageRank indicator has been phased out as of 2024. Therefore, there is no way to increase PageRank anymore.

Currently, Domain Authority (DA) and Page Authority (PA) are gaining attention as metrics for SEO evaluation. To improve DA and PA, the following conditions are necessary:

-Increase the number of keywords that rank on the Google search engine.

-Naturally acquire more high-quality backlinks.

Meeting these conditions is not something that can be achieved overnight. Therefore, it is crucial to continuously create high-quality content that meets the needs of users.

Moreover, it goes without saying nowadays, but please avoid the following SEO practices:

-Collecting low-quality links

-Hidden links

-Comment spam

Q: What is TBPR? 

A: TBPR stands for Toolbar PageRank, which was a tool provided by Google for viewing a page’s PageRank. The toolbar allowed users to check the PageRank value before it was discontinued.

Additionally, the PageRank used in the search algorithm, introduced to differentiate from TBPR, is sometimes referred to as Real PageRank.

Summary

PageRank was a metric based on backlinks to quantify the value of a web page. Although the concept of PageRank is no longer in public use, the significance of backlinks in evaluating a website remains. Therefore, globally renowned SEO companies like MOZ and Ahrefs have proposed metrics to replace PageRank. As of 2024, metrics such as Domain Authority (DA) and Page Authority (PA) are still highly valued in implementing effective SEO strategies.

Author Profile

SEO Consultant

Mr. Takeshi Amano, CEO of Admano Co., Ltd.

Mr. Takeshi Amano is a graduate of the Faculty of Law at Nihon University. With 12 years of experience working in the advertising agency industry, he discovered SEO and began his research during the early days of SEO. He self-taught and conducted experiments and verifications on over 100 websites. Using this expertise, he founded Admano Co., Ltd., which is currently in its 11th year of operation. Mr. Amano handles sales, SEO consulting, web analytics (holding the Google Analytics Individual Qualification certification), coding, and website development. The company has successfully managed SEO strategies for over 2000 websites to date.

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