Google Algorithm Updates
2021
Featured Snippet Drop — February 19, 2021
SERPs with Featured Snippets dropped 40% day over day, according to MozCast, to their lowest point since 2015. On closer inspection, these were disproportionately targeted at YMYL queries and heavily focused on short queries (especially 1-word queries) (health and finance).
- Featured Snippets Drop to Historic Lows (Moz)
- Google Search may be showing featured snippets less often (SEL)
Passage Indexing (US/English) — February 10, 2021
For US/English queries, Google launched “passage indexing” (which is probably closer to passage ranking). While there was a two-day period of moderate ranking movement, it was unclear how the update affected SERPs. Initially, Google estimated that this update would affect 7% of queries.
2020
Unnamed Update — December 17, 2020
MozCast measured moderately high rankings flux at 99°F one day after Google announced the end of the December Core Update rollout. It was unclear whether this was the final phase of the rollout or a separate, smaller algorithm update.
December 2020 Core Update — December 3, 2020
Google announced a Core Update that appeared to roll out quickly, with the bulk of the impact hitting on December 3rd. MozCast hit 112°F, on par with the March 2020 Core Update and August 2018 “Medic” Update. Some sites reported reversals a few days later, but this seems to have been limited.
- Google’s December 2020 Core Update: By the Numbers (Moz)
- 1,000+ Winners and Losers of the December 2020 Google Core Algorithm Update (Path Interactive)
- The Themes Running Through The December 2020 Core Update (Rank Ranger)
Indexing Bug, Pt. 2 — October 12, 2020
By October 14th, Google claimed to have fixed the majority of the indexing and canonicalization bugs. Around October 12th, MozCast detected a drop in indexed pages and a temperature of 104°F, with temperatures in the 90s persisting for a few days.
Indexing Bug, Pt. 1 — September 29, 2020
Beginning in early September, Google confirmed an indexing and canonicalization bug. On September 29th and 30th, MozCast recorded temperatures of 99°F and detected dips in indexed pages on September 23rd and 29th.
Unnamed Update — August 15, 2020
Although rank tracking tools and webmaster chatter indicated a significant update, MozCast measured 101°F, Google did not confirm it. Some industry analysts speculated that the changes were reversed the next day and were only temporary.
Google Glitch — August 10, 2020
On August 10, SEOs reported massive ranking changes that seemed to vanish after a few hours. A glitch in Google’s indexing systems was later confirmed by the company. The following day (August 11), MozCast recorded 97°F, but it’s unclear if this was related.
Google Bug Fix — June 22, 2020
The flux was visible in rank-tracking tools, with MozCast reaching 96°F. While there was no confirmation of an algorithm update, a Google representative confirmed that an indexing bug affecting Disqus comments would be fixed during this time period.
May 2020 Core Update — May 4, 2020
Google released a new Core Update (the second of 2020), which resulted in major ranking shifts from May 4-6. It was the second-highest Core Update on MozCast after the August 2018 “Medic” update, peaking at 113°.
COVID-19 Pandemic — March 11, 202
COVID-19, while not an algorithm update, had a significant impact on consumer search behavior. The World Health Organization’s pandemic declaration on March 11th appeared to be a watershed moment. On MozCast, 16 of the 31 days in March exceeded 90°F, and rankings were in flux well into April and May.
Unnamed Update — February 7, 2020
For a few days, multiple tools recorded extremely high ranking flux (MozCast peaked at 116° on February 7th). According to Google, this was not a Core Update, and some data sets indicated that the changes were reversed around February 12th.
Featured Snippet De-duping — January 22, 2020
In line with Google’s philosophy that a Featured Snippet is a promoted organic result, URLs in Featured Snippets will no longer appear as traditional organic results. This had significant implications for organic CTR and rank-tracking.
January 2020 Core Update — January 13, 2020
In line with the previous three core updates, Google rolled out another core update, with MozCast indicating heavy flux over three days and a high temperature of 97°F (but smaller than the August 2018 “Medic” core update).
2019
International BERT Roll-out — December 9, 2019
Google confirmed that the BERT natural language processing algorithm was being rolled out in 70 languages around the world. The SEO community had been speculating about this announcement, and the exact timing of the roll-out is unknown.
BERT Update — October 22, 2019
To support the BERT natural language processing (NLP) model, Google upgraded their algorithm and underlying hardware. BERT aids Google in better understanding and interpreting natural language searches.
Unnamed Update — October 2, 2019
Multiple days of ranking flux were recorded by SERP trackers, with MozCast showing early signs on October 2 and peaking at 98°F on October 4. Google did not confirm the update and did not provide any additional information.
September 2019 Core Update — September 24, 2019
Google has released yet another major update. On MozCast, the update measured 97°F (quite high, but not historically high) and appeared to affect sites that had been affected by previous core updates. Google didn’t give us a lot of information.
"Maverick" Update — July 12, 2019
Ranking trackers and webmaster chatter noted a week of high flux (MozCast peaked at 95°F on July 16), which the search community dubbed the “Maverick” update. Google did not confirm the update and provided few details.
Site Diversity Update — June 6, 2019
Google announced a “site diversity” update ahead of time, claiming it would help sites with more than two organic listings. According to Moz data, the update improved SERPs with 3-5 duplicate sites on page one marginally, but the effect was minor.
June 2019 Core Update — June 3, 2019
Google teased a “core” update, but only provided a few details. In some cases, sites impacted by previous core updates appear to have been affected, and some major UK publishers have reported significant losses. According to MozCast, the impact was smaller on average than the August “Medic” update.
Deindexing Bug — April 5, 2019
Around the weekend of April 5th, Google confirmed a bug that caused pages to be removed from the search index. According to Moz data, about 4% of stable URLs dropped off of page one on April 5th and 7th. The majority of the sites quickly recovered.
March 2019 Core Update — March 12, 2019
Google confirmed a “core” update, claiming that it was the third major core update since the term was coined. MozCast reached a high of 101.2°F, slightly lower than March 1st temperatures. There were no specifics about the nature of the update provided.
Unnamed Update — February 6, 2019
Following a relatively quiet December and January, tracking tools detected a significant increase in ranking flux, with MozCast reaching 103.4°F.
2018
Unnamed Update — November 29, 2018
Webmaster chatter and other tracking tools indicated high algorithm flux, with MozCast reaching 103.1°F. Google has not confirmed this.
Unnamed Update — October 15, 2018
MozCast spiked to 109.7°F, indicating heavy algorithm flux, according to tracking tools and webmaster chatter. There has been no confirmation from Google.
Unnamed Update — September 10, 2018
The temperature on MozCast reached 107.6°F, and webmaster chatter about an update exploded, but Google refused to confirm any major changes.
"Medic" Core Update — August 1, 2018
With widespread reports of massive impact, Google confirmed a “broad core algorithm update.” It went live over the course of about a week, peaking on August 1-2. Although there was a large-scale impact in all verticals, this update seemed to disproportionately affect sites in the health and wellness vertical.
Chrome Security Warnings (Full Site) — July 24, 2018
Chrome 68 began marking all non-HTTPS sites as “not secure” months after warning users about unsecured (non-HTTPS) forms. The changes went live on July 24, but they require users to update to the most recent version of Chrome, which can take weeks or months.
Unnamed Update — July 21, 2018
Algorithm trackers and webmaster chatter indicated that there was a lot of movement in the rankings, but Google did not confirm it. The highest temperature recorded by MozCast in 2018 was 114°F.
Mobile Speed Update — July 9, 2018
Google rolled out the mobile page speed update six months after announcing it, making page speed a ranking factor for mobile results. According to Google, this only affected the slowest mobile sites, and there was no evidence of significant changes in mobile rankings.
Video Carousels — June 14, 2018
Videos were moved from organic-like results with thumbnails to a dedicated video carousel, causing a reshuffle in previously tracked organic results. Simultaneously, the number of SERPs with videos increased by 60%, according to MozCast.
Unnamed Update — May 23, 2018
Although there was a lot of activity in algorithm tracking tools and webmaster chatter, Google did not confirm an update. Extremely high temperatures were recorded by MozCast over a three-day period, peaking on May 23.
Snippet Length Drop — May 13, 2018
Google rolled back most snippets to the previous limit after testing longer display snippets of up to 300+ characters for a few months (about 150-160 characters).
Unnamed Core Update — April 17, 2018
MozCast detected a spike in algorithm flux on April 17 that lasted for more than a week. Google later confirmed a “core” update, but didn’t provide any details, and neither Google nor the SEO community named the update.
Mobile-First Index Roll-out — March 26, 2018
The mobile-first index was finally “rolling out,” according to Google. It’s unclear how much of an impact this specific roll-out had on the overall index because the index has been in testing for months and Google has stated that they are migrating sites gradually. Within Google Search Console, webmasters should begin to receive notifications.
Zero-result SERP Test — March 14, 2018
Google began displaying zero organic results and a “Show all results” button on a small set of Knowledge Cards, including some time/date queries and unit conversion calculators. Google ended the test a week later, but we believe it is an important sign of things to come.
"Brackets" Core Update — March 8, 2018
On March 7th, Google confirmed a “core” update, but volatility spiked on March 4th, with a second spike on March 8th, and lasted nearly two weeks. This could have been a series of updates or a single long-running update. Glenn Gabe came up with the name “Brackets,” but Google provided no further information.
Unnamed Update — February 20, 2018
Around February 20th, rankings showed a spike in volatility (across a number of tools), which quickly subsided, possibly signaling a targeted algorithm update. During this time, Google has not confirmed any updates.
2017
"Maccabees" Update — December 14, 2017
Around December 14th, chatter and several tools revealed ranking volatility. This was dubbed the “Maccabees” update by Barry Schwartz, but Google would only confirm that a few minor changes had occurred in the overall timeline. Due to their disruptive effect on e-commerce, pre-holiday updates tend to get more attention (and are generally rarer).
Snippet Length Increase — November 30, 2017
Google increased the length of search snippets across a large number of results after testing them for over two years. As a result, we increased the length of the Meta Description from 155 to 300 characters (almost doubling). Google confirmed a change to the way snippets are handled, but didn’t elaborate.
Unnamed Update — November 14, 2017
A high amount of flux was detected by algorithm trackers and webmaster chatter, peaking (in our data) around November 15. An official update has yet to be confirmed by Google.
Featured Snippet Drop — October 27, 2017
Between October 27 and October 31, there was a significant drop in Featured Snippets. This was accompanied by an increase in Knowledge Panels, as Google appeared to add a large number of panels for broad terms and objects (“travel”, “toilet”, “web design”, etc.). Around December 15, some of these panels vanished.
Chrome Security Warnings (Forms) — October 17, 2017
Google began warning visitors to sites with unsecured forms with the release of Chrome 62. Despite the fact that this was not an algorithm change, it was an important step in Google’s push toward HTTPS and could have a significant impact on site traffic.
Unnamed Update — September 27, 2017
After a period of relative calm, algorithm trackers (including MozCast) and webmaster chatter noticed increasing flux starting around September 25th, which seemed to peak on the 27th. There has been no official confirmation of an update.
Google Jobs — June 20, 2017
Google has launched their jobs portal, which includes a separate 3-pack of job listings in search results. These findings drew information from nearly every major source, including LinkedIn, Monster, Glassdoor, and CareerBuilder.
Unnamed Update — May 17, 2017
A massive, multi-day spike began around May 17th, according to MozCast and other tools. This came before a long period of high algorithmic flux, which could have lasted months.
Google Tops 50% HTTPS — April 16, 2017
As of mid-April, half of page-1 Google organic results were secure/HTTPs, according to our MozCast 10K tracking set. By the end of 2017, this figure had risen to nearly 75%.
"Fred" (Unconfirmed) — March 8, 2017
Google rolled out what appeared to be a major update, with SEO experts reporting widespread effects. Gary Illyes joked about calling him “Fred,” and the nickname stuck, though he later clarified that this was not an official confirmation.
Unnamed Update — February 6, 2017
Beginning on February 1st, algorithm changes lasted for a week, peaking around February 6th (some reported the 7th). According to webmaster chatter and industry case studies, these were two distinct events.
Unnamed Update — February 1, 2017
Starting around February 1st and peaking around February 6th, there was a period of high algorithm flux. It’s unclear whether there were multiple algorithm updates or just one with a long rollout, but anecdotal evidence suggests there were at least two.
Intrusive Interstitial Penalty — January 10, 2017
Google has begun enforcing a penalty for aggressive interstitials and pop-ups that may negatively impact the mobile user experience. Google also gave a five-month heads-up on this update, which is unusual. High temperatures were recorded by MozCast on January 10-11, but many SEOs reported little impact on sites that should have been affected.
2016
Unnamed Update — December 14, 2016
Around December 14-15, multiple Google trackers revealed massive flux, including a rare MozCast temperature of 109°F. Although there was a lot of chatter among webmasters, Google did not confirm an update.
Unnamed Update — November 10, 2016
On November 10th, MozCast detected a major (106°) spike, followed by another on November 18th. During both periods, industry buzz was high, with some speculating that the second spike was a reversal of the first. Neither event has been confirmed by Google. Many people reported bad dates in SERPs around the same time, but it’s unclear whether this was a coincidence or not.
Penguin 4.0, Phase 2 — October 6, 2016
The reversal of all previous Penguin penalties was the second phase of Penguin 4.0. This appeared to happen after the new code was implemented, and it could have taken up to two weeks. On October 6th (116°), post-Penguin activity peaked once more, but it’s unclear whether this was due to Penguin or a new update. After October 6th, algorithm temperatures began to drop.
Penguin 4.0, Phase 1 — September 27, 2016
The first phase of Penguin 4.0 was the rollout of the new, “gentler” Penguin algorithm, which devalues bad links rather than penalizing sites, which happened around September 22-23. Although the exact timeline is unknown, we believe this update took at least a few days to complete and may have coincided with an algorithm temperature spike (113°) on September 27th.
Penguin 4.0 Announcement — September 23, 2016
Google finally announced a major Penguin update after nearly two years of waiting. The new Penguin, they claimed, is now real-time and integrated into the “core” algorithm. Although the initial impact assessments were minor, it was later revealed that the Penguin 4.0 rollout was unusually lengthy and multi-phased (see September 27th and October 6th).
Image/Universal Drop — September 13, 2016
With image (universal/vertical) results, MozCast recorded a near-record 111° temperature and a 50% drop in SERPs. The universal result shuffle created an organic position on page one, causing significant ranking shifts, but it’s more than likely that this was part of a larger update.
"Possum" — September 1, 2016
While Google has not confirmed it, MozCast reported extreme temperatures of 108° and a drop in local pack prevalence, as well as a major shift in pack results. According to data, this update (or a related update) had a significant impact on organic results as well.
Mobile-friendly 2 — May 12, 2016
Google rolled out another ranking signal boost to benefit mobile-friendly sites on mobile search just over a year after the original “mobile friendly” update. Because the vast majority of the sites we monitor are already mobile-friendly, the impact of the latest update is likely to be minor.
Unnamed Update — May 10, 2016
MozCast and other Google weather trackers showed a historically rare week-long pattern of algorithm activity, including a 97-degree spike. Google would not confirm this update, and no explanation is currently available.
AdWords Shake-up — February 23, 2016
On many commercial searches, Google made significant changes to AdWords, removing right-column ads entirely and replacing them with 4-ad top blocks. Although this was a paid search update, it had a big impact on CTR for both paid and organic results, especially for competitive keywords.
Unnamed Update — January 8, 2016
Multiple ranking tracking tools (including MozCast) reported historically large changes in rankings, which Google later confirmed as a “core algo update.” Although Google confirmed that this was not a Penguin update, the details are still sketchy.
2015
RankBrain* — October 26, 2015
Google made a big announcement, revealing that machine learning has been a part of the algorithm for months, helping to determine the third most important ranking factor. *Note: This is merely an announcement date; we believe the actual launch took place in the spring of 2015.
Panda 4.2 (#28) — July 17, 2015
Google announced a Panda update (most likely a data refresh), stating that the full rollout could take months. The immediate impact was unknown, and no signs of a major algorithm update were visible.
The Quality Update — May 3, 2015
Google acknowledged a core algorithm change impacting “quality signals” after numerous reports of large-scale ranking changes dubbed “Phantom 2.” This change appears to have had a wide impact, but Google hasn’t revealed any details about the signals involved.
Mobile Update AKA "Mobilegeddon" — April 22, 2015
In an unusual move, Google pre-announced an algorithm update, stating that mobile rankings for mobile-friendly sites would differ beginning April 21st. The impact of this update was much smaller than expected in the short term, and our data indicated that algorithm flux peaked on April 22nd.
Unnamed Update — February 4, 2015
Many webmasters and SERP-trackers have reported significant changes in Google’s SERPs. It was speculated that the update would focus on e-commerce or improve mobile usability. An update has not been officially confirmed by Google.
Significant Google Search Algorithm Update Yesterday (SER)
Google Brand-eCommerce “Update” causing fluctuations (Searchmetrics)
2014
Pigeon Expands (UK, CA, AU) — December 22, 2014
The “Pigeon” update to Google’s local algorithm was extended to the United Kingdom, Canada, and Australia. The first update was released in July of 2014 in the United States. The update was confirmed on February 22nd, but it could have gone live as early as February 19th.
Penguin Everflux — December 10, 2014
Penguin has shifted to continuous updates, rather than infrequent, major updates, according to a Google representative. While the exact timeline was unknown, this claim seemed to fit with the ongoing transition following Penguin 3.0. (including unconfirmed claims of a Penguin 3.1).
Pirate 2.0 — October 21, 2014
Google released a new update to combat software and digital media piracy, more than two years after the original DMCA/”Pirate” update. This update was extremely targeted, causing a significant drop in ranking for a small number of sites.
Penguin 3.0 — October 17, 2014
Google released a Penguin refresh more than a year after the previous Penguin update (2.1). This update appeared to be smaller than expected (affected 1% of US/English queries) and was most likely a data-only update (not a new Penguin algorithm). The update’s timing was unclear, especially internationally, and Google claimed it would take “weeks” to complete.
"In The News" Box — October 1, 2014
Google made what appeared to be a display change to the News-box results, but later announced that news links had been expanded to a much larger set of potential sites. News results in SERPs also increased, and major news sites reported significant traffic changes.
Panda 4.1 (#27) — September 23, 2014
A significant Panda update was announced by Google, which included an algorithmic component. They estimated that 3-5 percent of queries would be affected. The exact timing was unknown due to the “slow rollout.”
Authorship Removed — August 28, 2014
Following the removal of authorship photos on June 28th, Google announced that authorship markup would be completely removed (and would no longer process it). Authorship bylines had vanished from all SERPs by the next morning.
HTTPS/SSL Update — August 6, 2014
Following months of speculation, Google announced that secure sites would be prioritized, and that adding encryption would result in a “lightweight” ranking boost. They stressed that this boost would be modest at first, but that if the change proved to be beneficial, it could grow.
Pigeon — July 24, 2014
With an update that drastically altered some local results and changed how they handle and interpret location cues, Google shook the local SEO world. Pigeon, according to Google, strengthened ties between the local and core algorithms (s).
Authorship Photo Drop — June 28, 2014
After heavily promoting authorship as a connection to Google+, John Mueller made a surprise announcement (on June 25th) that Google would be removing all authorship photos from SERPs. Around the 28th of June, the drop was completed.
Payday Loan 3.0 — June 12, 2014
Google released another major update less than a month after the Payday Loan 2.0 anti-spam update. According to official statements, 2.0 was aimed at specific websites, while 3.0 was aimed at spammy queries.
Panda 4.0 (#26) — May 19, 2014
A major Panda update was confirmed by Google, which included both an algorithm update and a data refresh. According to official estimates, about 7.5 percent of English-language queries were impacted. While Matt Cutts stated that the rollout began on May 20, our data strongly suggests that it began earlier.
Payday Loan 2.0 — May 16, 2014
Google’s “payday loan” algorithm, which targets particularly spammy queries, was updated shortly before Panda 4.0. The exact date of the rollout was unknown (Google said “this past weekend” on 5/20), and the back-to-back updates made it difficult to figure out the details.
Unnamed Update — March 24, 2014
Around 3/24-3/25, major algorithm flux trackers and webmaster chatter peaked, leading some to believe that the new, “softer” Panda update had arrived. Many websites reported changes in their rankings, but Google never confirmed the change.
Page Layout #3 — February 6, 2014
Google’s page layout algorithm, also known as “top heavy,” has been “refreshed.” The page layout algorithm, which was first introduced in January 2012, penalizes websites that have too many ads above the fold.
2013
Authorship Shake-up — December 19, 2013
Over the course of a month, authorship mark-up vanished from roughly 15% of queries, as predicted by Matt Cutts at Pubcon Las Vegas. Although the fall peaked around December 19th, the numbers have remained volatile and have not recovered to their previous highs.
Unnamed Update — December 17, 2013
Almost all global flux trackers showed unusually high activity levels. Google declined to confirm an update, implying that they avoid doing so around the holidays. The number of Partial-Match Domains (PMDs) increased, according to MozCast, but the patterns were unclear.
Unnamed Update — November 14, 2013
Multiple Google trackers detected unusual activity, which coincided with a Google Webmaster Tools report of widespread DNS errors. Google has not confirmed an update, and the cause and nature of the disruption are unknown.
Penguin 2.1 (#5) — October 4, 2013
Google released another Penguin update after a four-and-a-half-month hiatus. Given the 2.1 designation, this was most likely a data update rather than a major Penguin algorithm change. Although some webmasters reported being hard hit, the overall impact appeared to be moderate.
Hummingbird — August 20, 2013
Google announced the “Hummingbird” update on September 26th, but it appears to have been released a month earlier. Our best guess is that it’s linked to a MozCast spike on August 20th, as well as numerous reports of flux between August 20 and 22. Hummingbird has been compared to Caffeine, and it appears to be a core algorithm update that will continue to power changes to semantic search and the Knowledge Graph for months.
In-depth Articles — August 6, 2013
Google has added a new type of news result called “in-depth articles,” which is devoted to longer-form, evergreen content. It included links to three articles when it first launched, and it appeared in about 3% of MozCast’s searches.
Unnamed Update — July 26, 2013
MozCast observed a large Friday spike (105° F), with other sources indicating that there was significant activity over the weekend. This update has not been confirmed by Google.
Knowledge Graph Expansion — July 19, 2013
Overnight, queries containing Knowledge Graph (KG) entries increased by more than half (+50.4 percent) across the MozCast data set, with more than a quarter of all searches containing some kind of KG entry.
Panda Recovery — July 18, 2013
A Panda update was confirmed by Google, but it was unclear whether it was one of the 10-day rolling updates or something new. The implication was that this was algorithmic, and that it may have “softened” some of the Panda penalties previously imposed.
Multi-Week Update — June 27, 2013
Matt Cutts of Google responded on Twitter, predicting a “multi-week” algorithm update between June 12th and “the week after July 4th.” The nature of the update was unknown, but there was a lot of volatility in the rankings during that time, peaking on June 27th (according to MozCast data). Google appears to have been experimenting with some changes that were later reversed.
"Payday Loan" Update — June 11, 2013
Google announced a targeted algorithm update aimed at niches with a history of spammy results, citing payday loans and porn as examples. The update was announced on June 11th, but Matt Cutts indicated that it would take 1-2 months to roll out.
Panda Dance — June 11, 2013
While not a Panda update, Matt Cutts clarified at SMX Advanced that Panda was still updating monthly, but each update was spread out over about ten days. Many people had expected a “everflux” after Panda #25, but this was not it.
Penguin 2.0 (#4) — May 22, 2013
The 4th Penguin update (dubbed “2.0” by Google) arrived with only moderate impact after months of speculation bordering on hype. The exact nature of the changes remained unknown, but evidence suggested that Penguin 2.0 was more finely targeted at the page level.
Domain Crowding — May 21, 2013
Deep in the SERPs (pages 2+), Google released an update to control domain crowding/diversity. It was unclear when it would be released, but it appeared to arrive just before Penguin 2.0 in the United States, and possibly on the same day internationally.
"Phantom" — May 9, 2013
There were numerous reports of an algorithm update around May 9th (also verified by high MozCast activity). Although the exact nature of this update was unknown, many websites experienced significant traffic loss as a result of it.
Panda #25 — March 14, 2013
At SMX West, Matt Cutts announced a Panda update, implying that it would be the final one before Panda was integrated into the core algorithm. The exact date is unknown, but MozCast data suggests it was between March 13 and March 14.
Panda #24 — January 22, 2013
According to Google, the first official update of 2013 affected 1.2 percent of queries. This didn’t seem to have anything to do with the talk of an update around 1/17-18. (which Google did not confirm).