Deep dive into Google algorithm updates: 2021

Google Updates

In the fast-evolving digital landscape, Google updates play a pivotal role in shaping the online experience for both users and webmasters. 2021 was no exception, witnessing significant changes that affected search rankings, user experience, and website visibility across Google Search. The importance of staying abreast with these updates cannot be overstated, as they directly influence the effectiveness of SEO strategies and the success of online businesses. This article aims to demystify the key Google updates of 2021, providing insights into their implications and how they have reshaped the digital marketing realm.

Commencing with a comprehensive review of the pivotal updates introduced in 2021, this article will delve into detailed analyses of core updates, the introduction of new features, and the expansion of mobile-first indexing. Additionally, it will examine the enhancements in spam detection and security measures taken by Google, alongside the pioneering user experience innovations aimed at improving web usability and accessibility. By exploring these critical changes, readers will gain a deeper understanding of the evolving dynamics of Google Search and the Search Console, equipping them with the knowledge to navigate the challenges and opportunities these google updates present.

Review of Key 2021 Updates

In 2021, Google introduced several significant updates that reshaped the landscape of search engine optimisation and user interaction. These changes aimed to enhance the quality and relevance of search results, prioritising user experience and cracking down on manipulative SEO practices.

Overview of Google Algorithm Changes

Throughout the year, Google rolled out multiple algorithm updates, each targeting different aspects of the search ecosystem. The Page Experience Update, initiated in June, focused on user experience metrics such as loading speed, interactivity, and visual stability of pages. This update integrated new signals known as Core Web Vitals into Google’s ranking criteria, emphasising the importance of a smooth user experience.

Another notable update was the Product Reviews Update in December, which aimed to promote high-quality, in-depth reviews over thinner content. This update encouraged content creators to produce more substantial and insightful reviews by rewarding such content with higher search rankings.

Google also implemented several core updates, with the June and July 2021 core updates being particularly impactful. These updates refined Google’s algorithms to better understand and rank page content, affecting a wide range of websites and prompting webmasters to adapt their SEO strategies.

Significant Impacts on SEO

The algorithm changes introduced by Google in 2021 had profound impacts on search engine optimisation practices. Websites that prioritised user experience and provided high-quality content saw improvements in their rankings, while those relying on outdated tactics faced challenges.

For instance, the emphasis on Core Web Vitals prompted many site owners to improve their website’s loading times, responsiveness, and visual stability. As these factors were incorporated into Google’s ranking algorithms, they became critical components of effective SEO strategies.

Furthermore, the updates targeting review and spam content pushed for a cleaner, more trustworthy search environment. Websites that adjusted their content strategies to align with Google’s guidelines benefited from increased visibility and user engagement.

In conclusion, the 2021 Google updates reinforced the importance of adapting to the evolving digital landscape. By focusing on user experience and content quality, Google not only improved the search experience for users but also set new standards for webmasters and SEO professionals to follow.

Detailed Analysis of Core Updates

March 2021 Core Update

In March 2021, Google rolled out a significant core update alongside the March Link Spam update. The impacts of this update began to manifest rapidly, with many webmasters experiencing severe traffic drops shortly after its initiation. This update was notable for its focus on enhancing the detection of low-quality AI-generated content within search results, a response to the rising prevalence of such content. Google also introduced a new site-wide signal aimed at quantifying user experience, reflecting their ongoing commitment to rewarding high-quality, user-focused content. Despite the comprehensive nature of the update, it highlighted that even well-optimised sites could suffer drops if their content did not meet the newly adjusted standards.

June 2021 Core Update

June 2021 saw a two-part core update, starting with the June update followed by a subsequent one in July. This sequence was unusual and indicated that not all planned improvements were ready to be implemented in June. The June 2021 Core Update was distinct from the Page Experience Update, which also rolled out in the same month focusing on user experience metrics like loading speed and visual stability.

The core update aimed to enhance the relevance and authority of content returned in search results. It had a noticeable impact across various industries, with the health, vehicles/auto, and travel sectors among the most affected. Data showed significant volatility in search rankings, with SERP volatility scores peaking on June 4th. This volatility highlighted the dynamic nature of Google’s search algorithms and their effect on online visibility.

Webmasters noted that the update led to a redistribution of visibility within sectors, not necessarily penalising or favouring entire industries but rather adjusting the visibility of individual market players based on content quality and relevance. The update underscored the importance of aligning with Google’s guidelines and striving for content excellence to maintain or improve search rankings.

Both updates reinforced the critical nature of adapting to Google’s evolving algorithms and underscored the importance of quality content and robust SEO strategies to sustain and enhance online visibility.

Introduction of New Features

In 2021, Google introduced several innovative features designed to enhance the transparency and functionality of its search engine. These advancements are particularly focused on providing users with more context about the search results they see and improving how specific passages within a web page are ranked.

About This Result Feature

Google’s “About This Result” feature marks a significant shift towards greater transparency in search operations. This feature, accessible by tapping the three dots on the top right corner of a search result snippet, offers users detailed information about the origins of the information displayed. It informs users about the website’s security, the existence of a Wikipedia page about the site, and whether the listing is paid. If a website lacks a Wikipedia entry, Google provides additional context such as the date it first indexed the site. This feature aims to aid users in making informed decisions about the trustworthiness of the information they find online.

Google Passage Ranking

Another pivotal update is Google’s implementation of Passage Ranking, formerly known as Passage Indexing. This feature allows Google to not just rank web pages but also specific passages from these pages. It addresses the challenge of very specific searches where the answer might be buried deep within a web page. By better understanding the relevancy of specific passages, Google can now surface these snippets in search results, even if the entire page covers a broader topic. This nuanced approach helps users find precise answers to their queries more effectively, enhancing the overall search experience.

Google’s focus on refining its algorithms to better cater to user-specific search queries demonstrates its commitment to improving accuracy and user satisfaction in search results. These features collectively aim to empower users with better tools for navigating the vast information available on the internet, ensuring that they can trust and effectively use the data they retrieve from Google Search.

Mobile-First Indexing Expansion

Google’s Mobile-First Indexing has now become a standard practice, marking a significant shift in how web content is interpreted and ranked. Initially introduced in November 2016, this approach prioritises the mobile version of a website’s content for indexing and ranking purposes. By March 2021, Google completed the transition, fully implementing Mobile-First Indexing across all web domains. This change is pivotal for website owners as it emphasises the necessity of optimising mobile versions of their websites to maintain and enhance search rankings.

Full Rollout Details

The rollout of Mobile-First Indexing signifies Google’s response to the increasing predominance of mobile internet usage, which has seen a significant surge over recent years. Data from Statista in 2021 highlighted that 55.68% of internet searches originated from mobile devices. This behavioural shift underscores the importance of mobile-friendly websites. Google now exclusively uses the mobile version of a site’s content, crawled with a smartphone agent, to evaluate and rank websites. This comprehensive transition has led to the de-prioritisation of desktop-only sites, which may see a decline in Google’s search rankings if they fail to provide a mobile-friendly version.

How to Optimise

To align with Google’s Mobile-First Indexing, website owners must ensure their mobile sites mirror the content quality and functionality of their desktop versions. Here are key strategies to optimise for mobile-first indexing:

  1. Consistency Across Versions: Ensure that both mobile and desktop versions of your site contain the same high-quality content. This includes text, images, and videos that should be accessible and optimised for mobile users.
  2. Enhance User Experience (UX): Focus on improving mobile UX by optimising site load speed, button sizes, font readability, and navigation structure. These factors are crucial as Google evaluates the mobile version for user experience before considering desktop versions.
  3. Technical Optimisation: Pay attention to technical details such as correct meta tags for mobile and desktop versions and ensuring that Google can smoothly access essential content for ranking. Avoid common pitfalls like unwanted redirects or blocking mobile versions with robots.txt.
  4. Monitor Mobile Usability: Use tools like Google’s Search Console to track mobile usability issues and rectify them promptly. This will aid in maintaining a robust presence in mobile search results.

By adhering to these best practices, businesses can effectively adapt to Mobile-First Indexing, thereby sustaining and potentially improving their online visibility and performance in an increasingly mobile-centric world.

Spam and Security Enhancements

Google’s commitment to enhancing the security and integrity of its search results is evident through its rigorous spam updates. These updates target various forms of spam, including link spam and content spam, ensuring that users receive reliable and useful search results. By deploying advanced technologies like the AI-powered SpamBrain system, Google has significantly improved its ability to detect and mitigate spammy activities.

Overview of Spam Updates

Throughout 2021 and into 2023, Google has consistently released spam updates aimed at eliminating low-quality, deceptive content from its search results. These updates are crucial for maintaining the credibility of Google’s search engine, as they help ensure that users are provided with accurate and valuable information. For website owners and digital marketers, understanding these updates is essential. Neglecting the latest spam policies can lead to sudden drops in traffic and rankings, as sites employing spammy tactics are penalised or devalued. Staying informed about these updates not only helps in avoiding penalties but also facilitates the adoption of best practices for content creation and link building, fostering a healthier and more sustainable online presence.

Emphasis on Secure Connections

In addition to combating spam, Google has placed a strong emphasis on secure connections, particularly with the introduction of features in Android 14 that enhance user security. For instance, the support for rejecting null-ciphered cellular connections ensures that voice and SMS traffic is always encrypted, protecting users from passive over-the-air interception. This move highlights Google’s dedication to safeguarding user data across all platforms, reinforcing the importance of security in maintaining user trust and compliance with global standards.

By continuously updating its spam detection and security measures, Google not only improves the user experience but also sets a higher standard for content quality and security practices across the internet.

User Experience Innovations

In 2021, Google introduced significant innovations aimed at enhancing user experience through advanced technological integrations and updates. These efforts are exemplified by the introduction of Core Web Vitals and the MUM algorithm, each playing a pivotal role in optimising the search experience across various devices and languages.

Core Web Vitals

Google’s Core Web Vitals are a set of specific factors that Google considers important in a webpage’s overall user experience. Metrics such as Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS) are crucial for developers to understand and optimise. LCP measures the load performance of content on a page, with a target time of under 2.5 seconds. FID assesses the responsiveness of a page when a user first interacts with it, aiming for less than 200 milliseconds. CLS focuses on the visual stability of a page, striving for a score lower than 0.1 to ensure a smooth visual experience.

These metrics not only highlight the technical aspects of user interaction but also serve as a benchmark for sites aiming to enhance their digital presence. By integrating these vitals into their ranking algorithm, Google has placed a premium on seamless user experiences, pushing developers to prioritise site speed and stability.

MUM Algorithm

The Multitask Unified Model (MUM) algorithm, introduced by Google, represents a leap forward in handling complex search queries. This AI-driven approach understands queries in up to 75 languages and can analyse and integrate information across different formats—text, image, and potentially video and audio in the future. MUM’s capability to process multimodal data means that it can offer answers to nuanced queries by assessing content that a traditional text-based search engine might overlook.

MUM’s design is geared towards reducing the need for multiple searches by providing comprehensive and contextually relevant answers in a single response. This not only enhances the efficiency of searches but also significantly improves the quality of results, making the search experience more intuitive and user-centric.

These innovations by Google underscore its commitment to improving the search engine’s functionality and responsiveness, ensuring that users have a more integrated and responsive online experience. By focusing on both the underlying technology with MUM and user interaction metrics through Core Web Vitals, Google continues to refine its search engine to better serve the needs of its global user base.


Throughout 2021, Google unveiled a series of updates and innovations, each aimed at enhancing user experience, the integrity of search results, and website visibility across its platform. By prioritising content quality, website performance, and security, these updates have set new benchmarks for webmasters and SEO professionals. The significant algorithm changes, introduction of innovative features like Core Web Vitals and MUM, and the focus on mobile-first indexing underscore the evolving nature of search engine optimisation and the imperative for websites to adapt. These initiatives not only aim to improve the end-user experience but also challenge digital marketers to employ ethical, user-focused strategies to succeed in the ever-changing digital landscape.

The implications of these updates extend far beyond immediate impacts on search rankings, signalling a shift towards a more secure, user-centred online environment. As Google continues to refine its algorithms and introduce new features, the importance of staying informed and agile in digital marketing approaches becomes increasingly apparent. For businesses and webmasters, the task ahead lies in aligning with these updates to optimise user experience and content relevance. As we move forward, the commitment to quality, security, and responsiveness will remain paramount in navigating the terrain of digital marketing and search optimisation, encouraging a web ecosystem that values both user satisfaction and content integrity.