Timeline

Every algorithm update, dated

195 documented changes to how search engines rank and present results, from 2003 to now. Updates the engine itself confirmed are marked as such; well-documented but unconfirmed volatility events are included and labelled honestly rather than dressed up as fact.

195
Recorded changes
183
Engine-confirmed
28
Core updates
8
Platforms
2003
Earliest recorded

2026 · 12 changes

June 2026 spam update

24 June 2026Google2-day rollout

Spam update rolled out in under two days, the second of 2026.

Spam UpdateConfirmed

May 2026 core update

21 May 2026Google12-day rollout

Second core update of 2026, completing in twelve days and reported as causing significant ranking volatility.

Core UpdateConfirmedHigh impact

Back button hijacking spam policy

13 April 2026Google

Google added a spam policy prohibiting pages that manipulate browser history to prevent users returning to search results.

PolicyConfirmed

March 2026 core update

27 March 2026Google12-day rollout

First core update of 2026, described by Google as a regular update to better surface relevant, satisfying content.

Core UpdateConfirmedHigh impact

March 2026 spam update

24 March 2026Google

Spam update that began and completed on the same day, the fastest rollout Google has recorded on its status dashboard.

Spam UpdateConfirmed

February 2026 Discover update

5 February 2026Google22-day rollout

First broad update Google announced specifically for the Discover feed rather than Search, taking three weeks to roll out.

Core UpdateConfirmedHigh impact

2025 · 32 changes

December 2025 core update

11 December 2025Google18-day rollout

Third and final core update of 2025, running for eighteen days across the holiday period.

Core UpdateConfirmedHigh impact

Social channels in Search Console

1 December 2025Google

Search Console began reporting on how a brand's social and creator channels perform in Google Search.

Product LaunchConfirmed

Custom annotations in Search Console

1 November 2025Google

Search Console let site owners annotate performance charts with their own events such as migrations and releases.

Product LaunchConfirmed

Query groups in Search Console Insights

1 October 2025Google

Search Console Insights began clustering related queries into groups so performance could be read at topic level.

Product LaunchConfirmed

US v. Google remedies ruling

2 September 2025Other

The court ordered Google to share search index and user interaction data with competitors and barred exclusive default search contracts.

PolicyConfirmedHigh impact

num=100 search parameter stops working

1 September 2025Google

Google silently stopped honouring the num=100 URL parameter, breaking the standard method for retrieving 100 results in one request.

Data ChangeUnconfirmedHigh impact

Store widget in Google Search

1 September 2025Google

Google launched a merchant store widget surfacing shipping, returns and ratings information alongside retailer results.

Product LaunchConfirmed

August 2025 spam update

26 August 2025Google27-day rollout

First spam update in eight months, taking nearly four weeks to roll out.

Spam UpdateConfirmed

Bing Search APIs retired

11 August 2025Bing

Microsoft shut down the Bing Search and Bing Custom Search APIs, removing a major independent source of SERP data for tooling vendors.

DeprecationConfirmed

Cloudflare blocks AI crawlers by default

1 July 2025Other

Cloudflare made blocking AI crawlers the default for new domains, ending open-by-default access to a large share of the web.

PolicyConfirmedHigh impact

Cloudflare Pay Per Crawl

1 July 2025Other

Cloudflare launched a private beta letting publishers charge AI crawlers per request using the HTTP 402 Payment Required status code.

Product LaunchConfirmed

Google Trends API (alpha)

1 July 2025Google

Google opened an alpha API for Google Trends data, giving programmatic access to scaled search interest for the first time.

Product LaunchConfirmed

Perplexity Comet browser

1 July 2025Perplexity

Perplexity released an agentic browser that navigates and acts on websites on the user's behalf, released free in October 2025.

Product LaunchConfirmed

June 2025 core update

30 June 2025Google17-day rollout

Second core update of 2025, running for over two weeks and reported as substantially larger than the March release.

Core UpdateConfirmedHigh impact

New Search Console Insights report

1 June 2025Google

Google rebuilt Search Console Insights as a full report inside Search Console with richer trend and content analysis.

Product LaunchConfirmed

Simplifying the search results page

1 June 2025Google

Google began removing rarely used rich result types and SERP enhancements as part of a deliberate simplification programme.

DeprecationConfirmed

AI Mode launches for all US users

20 May 2025Google

Google took AI Mode out of Labs and made it available to everyone in the United States, powered by a custom Gemini 2.5 model.

AI FeatureConfirmedHigh impact

App deep link documentation for Search

1 May 2025Google

Google published guidance on connecting a website and its mobile app so search results can open the app at the right screen.

DocumentationConfirmed

Copilot Search in Bing

4 April 2025Bing

Microsoft introduced Copilot Search as a mode within Bing that combines conventional results with generated, cited answers.

AI FeatureConfirmed

Hourly data in the Search Analytics API

1 April 2025Google

Google exposed hourly Search Console performance data through the Search Analytics API, not just the web interface.

Product LaunchConfirmed

Claude web search and Claude-SearchBot

20 March 2025Anthropic

Anthropic added live web search to Claude with cited sources, alongside separate crawler identities for search and user-initiated fetches.

AI FeatureConfirmed

March 2025 core update

13 March 2025Google14-day rollout

First core update of 2025, rolled out over two weeks with Google noting an emphasis on surfacing satisfying content from creators.

Core UpdateConfirmed

AI Mode launched in Search Labs

5 March 2025Google

Google began testing AI Mode, a fully conversational search surface with no conventional results list, as a Labs experiment.

AI FeatureConfirmedHigh impact

Robots Refresher documentation series

1 February 2025Google

Google published a multi-part series restating how the Robots Exclusion Protocol works and how to use page-level controls correctly.

DocumentationConfirmed

2024 · 37 changes

December 2024 spam update

19 December 2024Google7-day rollout

Week-long spam update starting the day after the December core update finished, running through the holiday period.

Spam UpdateConfirmed

ChatGPT search opened to all free users

16 December 2024OpenAI

OpenAI made web search available to all logged-in ChatGPT users at no cost, greatly expanding the audience for AI-cited content.

AI FeatureConfirmedHigh impact

December 2024 core update

12 December 2024Google6-day rollout

Unusually fast core update completing in six days, launched a week after the November update finished.

Core UpdateConfirmed

Site reputation abuse policy update

19 November 2024Google

Google clarified that first-party involvement or editorial oversight does not exempt third-party content from the site reputation abuse policy.

PolicyConfirmedHigh impact

November 2024 core update

11 November 2024Google24-day rollout

Core update running from 11 November to 5 December 2024, again spanning the peak retail period.

Core UpdateConfirmedHigh impact

ChatGPT search launch

31 October 2024OpenAI

OpenAI shipped web search inside ChatGPT for paying users, with in-line citations and source sidebars.

AI FeatureConfirmedHigh impact

Sitelinks search box removed

21 October 2024Google

Google retired the sitelinks search box that had let users search within a site directly from the results page.

DeprecationConfirmed

CJEU upholds Google Shopping fine

10 September 2024Other

The EU Court of Justice made final the €2.4bn Google Shopping self-preferencing decision, ending a case running since 2010.

PolicyConfirmed

August 2024 core update

15 August 2024Google19-day rollout

Core update explicitly framed as an attempt to better surface small independent publishers after feedback on the September 2023 helpful content update.

Core UpdateConfirmedHigh impact

US v. Google search monopoly ruling

5 August 2024Other

A US federal judge ruled that Google had illegally maintained a monopoly in general search services and general text advertising.

PolicyConfirmedHigh impact

Explicit fake content ranking updates

31 July 2024Google

Google made removal of non-consensual explicit imagery easier and demoted sites that receive many such removal requests.

AlgorithmConfirmed

Perplexity Publishers Program

30 July 2024Perplexity

Perplexity launched revenue sharing with publishers whose content is cited in its answers, following plagiarism accusations.

PolicyConfirmed

SearchGPT prototype and OAI-SearchBot

25 July 2024OpenAI

OpenAI announced a search prototype with publisher controls and introduced OAI-SearchBot as a separate crawler for search indexing.

AI FeatureConfirmedHigh impact

Bing generative search

24 July 2024Bing

Microsoft began testing a fully AI-generated Bing results page that reorganises web content into a synthesised layout with citations.

AI FeatureConfirmed

Mobile accessibility required for indexing

5 July 2024Google

Google completed the mobile-first transition: from July 2024 a page must be accessible to a mobile device to be indexed at all.

InfrastructureConfirmed

Cloudflare one-click AI crawler blocking

3 July 2024Other

Cloudflare gave all customers, including free plans, a single toggle to block AI training crawlers at the network edge.

PolicyConfirmedHigh impact

June 2024 spam update

20 June 2024Google7-day rollout

Week-long spam update enforcing Google's published spam policies across all languages.

Spam UpdateConfirmed

AI Overviews launch

14 May 2024Google

Google graduated SGE into AI Overviews and rolled it out to all US users by default, with international expansion following.

AI FeatureConfirmedHigh impact

Site reputation abuse spam policy

5 May 2024Google

Google banned publishing third-party content on an established site mainly to exploit that site's ranking signals, widely known as parasite SEO.

PolicyConfirmedHigh impact

INP replaces FID as a Core Web Vital

12 March 2024Google

Interaction to Next Paint became an official Core Web Vital on 12 March 2024, and First Input Delay was retired.

Data ChangeConfirmed

Expired domain abuse spam policy

5 March 2024Google

Google prohibited buying expired domains and repurposing them with unrelated content in order to inherit their historical ranking signals.

PolicyConfirmed

March 2024 core update

5 March 2024Google45-day rollout

The longest and most complex core update Google had run, taking 45 days and folding the helpful content system into core ranking.

Core UpdateConfirmedHigh impact

March 2024 spam update

5 March 2024Google14-day rollout

Spam update released alongside three new spam policies covering scaled content abuse, site reputation abuse and expired domain abuse.

Spam UpdateConfirmedHigh impact

Scaled content abuse spam policy

5 March 2024Google

Google replaced its automatically generated content policy with one covering content produced at scale to manipulate rankings, regardless of production method.

PolicyConfirmedHigh impact

Product variant structured data support

1 February 2024Google

Google added structured data support for describing product variants such as size and colour on a single product page.

Data ChangeConfirmed

2023 · 23 changes

Bing Chat rebranded as Copilot

15 November 2023Bing

Microsoft renamed Bing Chat to Copilot and began separating the assistant from the Bing search brand.

Product LaunchConfirmed

November 2023 reviews update

8 November 2023Google29-day rollout

Final announced reviews update before Google made the reviews system continuous and stopped announcing releases.

SystemConfirmed

November 2023 core update

2 November 2023Google25-day rollout

Fourth core update of 2023, running for nearly four weeks and using a different core ranking system from the October release.

Core UpdateConfirmedHigh impact

October 2023 core update

5 October 2023Google13-day rollout

Third core update of 2023, launched a day after a spam update and completed in under two weeks.

Core UpdateConfirmedHigh impact

October 2023 spam update

4 October 2023Google15-day rollout

Spam update focused on cloaking, hacked content, auto-generated spam and scraped content in several under-served languages.

Spam UpdateConfirmed

Google-Extended crawler control introduced

28 September 2023Google

Google introduced a robots.txt token letting publishers opt out of having crawled content used to train Gemini and Vertex AI generative models.

PolicyConfirmedHigh impact

ChatGPT browsing with Bing

27 September 2023OpenAI

OpenAI re-enabled live web browsing in ChatGPT using Bing as the retrieval layer, with citations back to source pages.

AI FeatureConfirmed

September 2023 helpful content update

14 September 2023Google13-day rollout

Third and most severe helpful content update, accompanied by revised guidance on AI-generated and hosted third-party content.

SystemConfirmedHigh impact

Naver Cue: generative search

1 September 2023Other

South Korea's Naver launched a generative search service built on its HyperCLOVA X model, integrated into its dominant domestic portal.

AI FeatureConfirmed

August 2023 core update

22 August 2023Google16-day rollout

Second core update of 2023, rolling out over sixteen days with significant movement for independent publishers.

Core UpdateConfirmedHigh impact

HowTo and FAQ rich result deprecation

8 August 2023Google

Google removed HowTo rich results entirely and restricted FAQ rich results to authoritative government and health sites.

DeprecationConfirmedHigh impact

GPTBot crawler introduced

7 August 2023OpenAI

OpenAI published a named crawler and robots.txt token so publishers could opt out of having their content used for model training.

PolicyConfirmedHigh impact

INP announced as replacement for FID

10 May 2023Google

Google announced that Interaction to Next Paint would replace First Input Delay as the Core Web Vitals responsiveness metric in March 2024.

DocumentationConfirmed

Search Generative Experience (SGE) launch

10 May 2023Google

Google launched a generative AI answer layer above search results as an opt-in Search Labs experiment in the United States.

AI FeatureConfirmedHigh impact

April 2023 reviews update

12 April 2023Google13-day rollout

Product reviews system was broadened to cover reviews of services, businesses, destinations and media, and renamed the reviews system.

SystemConfirmedHigh impact

March 2023 core update

15 March 2023Google13-day rollout

First core update of 2023, rolled out over two weeks with wide volatility across content categories.

Core UpdateConfirmedHigh impact

February 2023 product reviews update

21 February 2023Google14-day rollout

Product reviews update expanded beyond English to Spanish, German, French, Italian, Vietnamese, Indonesian, Russian, Dutch, Portuguese, Polish and more.

SystemConfirmedHigh impact

Bing Chat launch (the new Bing)

7 February 2023Bing

Microsoft rebuilt Bing around an OpenAI-powered chat experience, the first generative answer layer shipped by a major search engine.

AI FeatureConfirmedHigh impact

Yandex source code leak

25 January 2023Yandex

A 44GB archive of Yandex source code leaked publicly, exposing roughly 1,900 ranking factors from a major search engine.

Data ChangeUnconfirmed

2022 · 13 changes

December 2022 link spam update (SpamBrain)

14 December 2022Google29-day rollout

Link spam update powered by SpamBrain that neutralised both unnatural outbound links and links to spam sites.

Spam UpdateConfirmedHigh impact

Continuous scroll on desktop

5 December 2022Google

Google brought continuous scrolling to desktop search results in US English, replacing the traditional pagination control.

Product LaunchConfirmed

December 2022 helpful content update

5 December 2022Google38-day rollout

Second helpful content update, extended to all languages and taking almost six weeks to complete.

SystemConfirmedHigh impact

October 2022 spam update

19 October 2022Google2-day rollout

Fast global spam update completing in two days, applying to all languages.

Spam UpdateConfirmed

September 2022 product reviews update

20 September 2022Google6-day rollout

Product reviews update that ran concurrently with the September 2022 core update, complicating attribution.

SystemConfirmed

September 2022 core update

12 September 2022Google14-day rollout

Second core update of 2022, arriving days after the first helpful content update finished rolling out.

Core UpdateConfirmed

August 2022 helpful content update

25 August 2022Google15-day rollout

Launch of the helpful content system, a site-wide signal demoting content made mainly for search engines rather than people.

SystemConfirmedHigh impact

May 2022 core update

25 May 2022Google15-day rollout

First core update of 2022, rolled out over roughly two weeks with substantial volatility across news and health.

Core UpdateConfirmedHigh impact

March 2022 product reviews update

23 March 2022Google14-day rollout

Fourth product reviews update, rolled out over two weeks with expanded guidance for reviewers.

SystemConfirmedHigh impact

2021 · 17 changes

December 2021 product reviews update

1 December 2021Google20-day rollout

Third product reviews update, adding guidance on multi-retailer links and evidence of hands-on testing.

SystemConfirmedHigh impact

Vicinity local search update

30 November 2021Google8-day rollout

Local ranking change that increased the weight of proximity, reducing visibility for businesses far from the searcher.

AlgorithmConfirmedHigh impact

November 2021 core update

17 November 2021Google13-day rollout

Core update released two weeks before the holiday peak, completing on 30 November after a fast, volatile start.

Core UpdateConfirmedHigh impact

November 2021 spam update

3 November 2021Google8-day rollout

Broad spam update rolled out over about a week, listed on Google's official ranking updates dashboard.

Spam UpdateConfirmed

IndexNow protocol launched

18 October 2021Bing

Microsoft and Yandex launched an open push protocol letting sites notify participating search engines the moment a URL is added, updated or deleted.

Product LaunchConfirmed

Continuous scroll on mobile

14 October 2021Google

Google replaced mobile pagination with continuous scrolling through roughly four pages of results in US English.

Product LaunchConfirmed

Title link generation change

1 August 2021Google

Google began rewriting search result titles using on-page text such as H1s rather than relying on the title element.

Data ChangeConfirmed

July 2021 link spam update

26 July 2021Google29-day rollout

Month-long link spam update that nullified manipulative links, with particular attention to affiliate and sponsored content.

Spam UpdateConfirmedHigh impact

July 2021 core update

1 July 2021Google11-day rollout

Second half of the split 2021 core update, completing the changes Google could not ship in June.

Core UpdateConfirmedHigh impact

Structured Data Testing Tool retired

1 July 2021Google

Google retired its Structured Data Testing Tool in favour of the Rich Results Test and handed the generic validator to Schema.org.

DeprecationConfirmed

June 2021 spam updates

23 June 2021Google5-day rollout

Two rapid spam updates released within a week, overlapping with the June 2021 core update.

Spam UpdateConfirmed

Page experience update (mobile) rollout

15 June 2021Google77-day rollout

Core Web Vitals and other page experience signals began affecting mobile ranking, rolled out gradually over two and a half months.

AlgorithmConfirmed

June 2021 core update

2 June 2021Google10-day rollout

First half of a split core update, with Google saying some planned components were not ready and would follow in July.

Core UpdateConfirmedHigh impact

MUM (Multitask Unified Model)

18 May 2021Google

Multimodal, multilingual model announced at Google I/O 2021 and first applied to complex informational queries.

SystemConfirmed

April 2021 product reviews update

8 April 2021Google

First release of the product reviews system, rewarding in-depth reviews with original research over thin round-ups.

SystemConfirmedHigh impact

SpamBrain

1 April 2021Google

Google's machine-learning spam prevention system, first named publicly in its 2020 webspam report and used to power later spam and link spam updates.

SystemConfirmed

Passage ranking launches

10 February 2021Google

Passage-level ranking went live for US English queries, later expanding to other languages and markets.

SystemConfirmed

2020 · 9 changes

December 2020 core update

3 December 2020Google13-day rollout

Large core update released in the middle of the holiday retail season, completing after about two weeks.

Core UpdateConfirmedHigh impact

Page experience ranking signal announced

10 November 2020Google

Google confirmed page experience, including Core Web Vitals, would become a ranking signal from May 2021, later delayed to June.

DocumentationConfirmedHigh impact

Subtopics ranking

1 November 2020Google

Neural system that identifies subtopics within a broad query so results cover a wider range of angles.

SystemConfirmed

Yandex YATI

1 November 2020Yandex

Transformer-based relevance model that Yandex described as its biggest ranking improvement in ten years.

SystemConfirmed

Passage ranking announced

15 October 2020Google

Google announced it would index and rank individual passages within a page, not just whole pages.

SystemConfirmed

Core Web Vitals introduced

5 May 2020Google

Google defined a standard set of user-experience metrics — LCP, FID and CLS — as the Core Web Vitals.

DocumentationConfirmedHigh impact

May 2020 core update

4 May 2020Google

Unusually large core update released during the pandemic, with heavy movement in travel, events and local queries.

Core UpdateConfirmedHigh impact

Featured snippet deduplication

22 January 2020Google

A page promoted into a featured snippet stopped also appearing as a regular result on page one, removing the double listing.

Data ChangeConfirmed

January 2020 core update

13 January 2020Google

Broad core update announced on the day of release, reported as relatively mild outside your-money-or-your-life topics.

Core UpdateConfirmed

2019 · 7 changes

BERT expands to 70+ languages

9 December 2019Google

Google extended BERT-based query understanding from US English to more than 70 languages worldwide.

SystemConfirmed

Yandex Vega

1 December 2019Yandex

Major Yandex ranking release that added neural pre-ranking, expert content assessment and faster index freshness.

AlgorithmConfirmed

BERT

25 October 2019Google

Transformer-based language model applied to ranking and featured snippets, affecting around 10% of English queries at launch.

SystemConfirmedHigh impact

September 2019 core update

24 September 2019Google

Broad core update that Google pre-announced and that tracking tools recorded as milder than the March and June 2019 releases.

Core UpdateConfirmed

Site diversity change

6 June 2019Google

Google limited how many results from the same domain could appear in the top results, generally to two per query.

AlgorithmConfirmed

June 2019 core update

3 June 2019Google

First core update Google pre-announced, giving publishers a day's notice before the rollout began.

Core UpdateConfirmedHigh impact

March 2019 core update

12 March 2019Google

Broad core update that Google retroactively named after the industry had already labelled it Florida 2, standardising month-based naming.

Core UpdateConfirmedHigh impact

2018 · 6 changes

Neural matching

24 September 2018Google

AI system that connects words in a query to concepts in documents, revealed as affecting about 30% of queries.

SystemConfirmed

August 2018 broad core update (Medic)

1 August 2018Google

Large core update that disproportionately affected health, medical and other your-money-or-your-life sites, nicknamed Medic.

Core UpdateConfirmedHigh impact

Speed Update

9 July 2018Google

Page speed became a ranking factor for mobile search, affecting only the slowest pages.

AlgorithmConfirmed

April 2018 broad core update

20 April 2018Google

Second broad core update of 2018, confirmed by Google only after the industry noticed widespread ranking movement.

Core UpdateConfirmed

Mobile-first indexing rollout begins

26 March 2018Google

Google began migrating sites to mobile-first indexing, notifying each site through Search Console as it switched.

InfrastructureConfirmedHigh impact

March 2018 broad core update

12 March 2018Google

Google publicly confirmed a broad core algorithm update, establishing the naming convention used for every core update since.

Core UpdateConfirmedHigh impact

2017 · 3 changes

Maccabees

1 December 2017Google

Unconfirmed December 2017 update reported to affect sites built on large numbers of keyword-permutation landing pages.

AlgorithmUnconfirmed

Fred

1 March 2017Google

Unconfirmed March 2017 quality update associated with heavy losses at ad-dense, thin affiliate and low-value content sites.

AlgorithmUnconfirmedHigh impact

Intrusive interstitials penalty

10 January 2017Google

Mobile pages that hid content behind intrusive pop-ups or interstitials could rank lower, announced five months before launch.

AlgorithmConfirmed

2016 · 5 changes

Mobile-first indexing announced

4 November 2016Google

Google announced it would begin using the mobile version of a page as the primary basis for indexing and ranking.

InfrastructureConfirmedHigh impact

Penguin 4.0 (real-time, into core)

23 September 2016Google

Penguin became part of the core algorithm, ran in real time and moved from demoting sites to devaluing spammy links.

SystemConfirmedHigh impact

Possum

1 September 2016Google

Unconfirmed local ranking change that altered filtering by physical address and expanded results for businesses outside city limits.

AlgorithmUnconfirmed

Mobile-friendly update 2

12 May 2016Google

Google increased the weight of the mobile-friendly ranking signal in mobile search results.

AlgorithmConfirmed

Panda folded into core ranking

11 January 2016Google

Google confirmed Panda had become part of its core ranking algorithm, ending separate named refreshes.

SystemConfirmed

2015 · 3 changes

RankBrain

26 October 2015Google

Machine-learning system that interprets unfamiliar queries by relating them to concepts Google already understands.

SystemConfirmedHigh impact

Panda 4.2

17 July 2015Google

Final standalone Panda refresh, rolled out deliberately slowly over several months so no completion date was declared.

AlgorithmConfirmed

Mobile-friendly update (Mobilegeddon)

21 April 2015Google

Mobile-friendliness became a ranking signal for mobile searches, announced almost two months ahead of launch.

AlgorithmConfirmedHigh impact

2014 · 5 changes

Penguin 3.0

17 October 2014Google

Long-delayed Penguin refresh, the first in more than a year, which let sites that had cleaned up their links recover.

Spam UpdateConfirmed

Panda 4.1

23 September 2014Google

Panda refresh and algorithm tweak that Google said affected 3–5% of queries and was designed to help small, high-quality sites.

AlgorithmConfirmed

HTTPS as a ranking signal

6 August 2014Google

Google announced that serving a site over HTTPS would be used as a lightweight positive ranking signal.

AlgorithmConfirmed

Pigeon (local search update)

24 July 2014Google

Rebuilt local ranking so that traditional web ranking signals, including links and on-page factors, applied more directly to local results.

AlgorithmConfirmedHigh impact

Panda 4.0

20 May 2014Google

Major Panda algorithm revision, not just a data refresh, which Google said affected about 7.5% of English queries.

AlgorithmConfirmedHigh impact

2013 · 3 changes

Hummingbird

26 September 2013Google

Rewrite of Google's core query-processing engine to interpret the meaning of a whole query rather than matching individual keywords.

SystemConfirmedHigh impact

Payday Loan update

11 June 2013Google

Targeted heavily spammed query classes such as payday loans, pharmaceuticals, gambling and adult search.

Spam UpdateConfirmed

Penguin 2.0

22 May 2013Google

Second-generation Penguin that looked beyond home pages and analysed link spam at the level of individual pages across a site.

Spam UpdateConfirmedHigh impact

2012 · 5 changes

Exact Match Domain (EMD) update

28 September 2012Google

Removed the ranking advantage of low-quality domains whose names exactly matched a commercial search phrase.

AlgorithmConfirmed

Pirate (DMCA demotion signal)

10 August 2012Google

Ranking demotion for sites with large numbers of valid copyright removal notices, aimed at piracy portals.

AlgorithmConfirmed

Penguin link spam system

24 April 2012Google

Webspam algorithm targeting manipulative link building and over-optimised anchor text; launched April 2012 and later made real-time inside core ranking.

SystemConfirmedHigh impact

Venice

27 February 2012Google

Localised ordinary web results by the searcher's inferred location, making local intent apply to queries without an explicit place name.

AlgorithmConfirmedHigh impact

Page Layout (Top Heavy)

19 January 2012Google

Demotion for pages that pushed content below the fold with excessive above-the-fold advertising.

AlgorithmConfirmed

2011 · 3 changes

Freshness update

3 November 2011Google

Query deserves freshness change that Google said affected around 35% of searches by favouring recent content for time-sensitive queries.

AlgorithmConfirmed

Panda 2.0 (international rollout)

11 April 2011Google

Panda extended beyond the United States to all English-language queries worldwide, with user blocking data incorporated as a signal.

AlgorithmConfirmedHigh impact

Panda content quality system

24 February 2011Google

Site-wide content quality classifier that demoted thin, duplicated and low-value pages; launched February 2011 and later folded into core ranking.

SystemConfirmedHigh impact

2010 · 2 changes

Caffeine indexing system

8 June 2010Google

Rebuilt indexing infrastructure that indexed pages continuously instead of in batches, producing an index Google described as 50% fresher.

InfrastructureConfirmedHigh impact

May Day

1 May 2010Google

Change to how Google assessed long-tail queries that cut traffic to thin, template-generated category and tag pages.

AlgorithmConfirmed

2009 · 2 changes

Vince

20 February 2009Google

Change that gave large, well-known brands substantially more visibility for generic head terms.

AlgorithmConfirmedHigh impact

rel="canonical" introduced

12 February 2009Google

Google, Yahoo and Microsoft introduced the canonical link element so publishers could consolidate duplicate URLs onto a preferred version.

PolicyConfirmedHigh impact

2008 · 1 change

Dewey

31 March 2008Google

Large but never-explained spring 2008 reshuffle of results, reported by the industry as a broad ranking change.

AlgorithmUnconfirmed

2007 · 2 changes

Paid link PageRank penalties

7 October 2007Google

Google visibly reduced toolbar PageRank for sites judged to be selling links, signalling enforcement against the paid-link market.

Penalty ActionConfirmed

Universal Search

16 May 2007Google

Google began blending news, images, video, local and book results into the main results page, ending the era of ten uniform blue links.

Product LaunchConfirmedHigh impact

2005 · 3 changes

Big Daddy

1 December 2005Google90-day rollout

Infrastructure rebuild of Google's crawling and indexing stack that changed how redirects, canonicalisation and URL handling were processed.

InfrastructureConfirmed

Jagger

1 October 2005Google

Multi-phase autumn 2005 update aimed at reciprocal links, paid links and link farms, rolled out in roughly three stages.

AlgorithmUnconfirmedHigh impact

rel="nofollow" link attribute introduced

18 January 2005Google

Google, Yahoo and MSN jointly introduced rel="nofollow" so that publishers could mark links that should not pass ranking credit.

PolicyConfirmedHigh impact

2004 · 1 change

Austin

1 January 2004Google

January 2004 follow-up to Florida that further targeted hidden text, meta-tag stuffing and other on-page manipulation.

AlgorithmUnconfirmed

2003 · 1 change

Florida

15 November 2003Google

The first update to cause mass ranking loss for commercial sites, targeting keyword stuffing and early link manipulation just before the 2003 holiday season.

AlgorithmUnconfirmedHigh impact
What this list is not. It is a record of what changed and when — not a diagnosis of why your traffic moved. Ranking movements correlate with update windows far more often than they are caused by them, and several entries here were reconstructed from litigation documents and leaked material rather than announced. Where that is the case, the entry says so.