Trying to keep on top of all the Google algorithm updates is becoming quite a task. 

As we need a quick reference we thought we would put this time line together.  You will find helpful links to authoritative websites who go into greater detail about some of the recent changes Google has made.

Knowing the dates of these Google updates can help explain changes in rankings and organic website traffic and ultimately improve search engine optimisation.  Below, we have listed the major algorithmic changes that have had the biggest impact on search.

Mobile-First Index Roll-out — March 26, 2018

Google announced that the mobile-first index was finally "rolling out." Since the index has been in testing for many months, and Google has suggested they are migrating sites gradually, it's unclear how much impact this specific roll-out had on the overall index.  Webmaster should begin to see notifications within Google Search Console.

Zero-result SERP Test — March 14, 2018

On a small set of Knowledge Cards, including some time/date queries and unit conversion calculators, Google started displaying zero organic results and a "Show all results" button.  A week later, Google stopped this test, but it is an important sign of things to come.

"Brackets" Core Update — March 7, 2018

Google confirmed a "core" update on March 7th, but volatility spiked as early as March 4th and continued for almost two weeks.  This may have been multiple updates or one prolonged, rolling update.  The "Brackets" name was given by Glenn Gabe; no specific name or details were provided by Google.

Panda 4.2(#28) - July 17, 2015

Google announced what was most likely a Panda data refresh, saying that it could take months to fully roll out.  The immediate impact was unclear, and there were no clear signs of a major algorithm update.

The Quality Update - May 3, 2015

After many reports of large scale ranking changes, Google acknowledged a core algorithm change impacting quality signals.

Mobile Update AKA "Mobilegeddon" — April 22, 2015

In a rare move, Google pre-announced an algorithm update, telling us that mobile rankings would differ for mobile-friendly sites starting on April 21st.  The impact of this update was, in the short-term, much smaller than expected, and data showed that algorithm flux peaked on April 22nd.

7 Days After Mobilegeddon - Did The Sky Fall?

Penguin Everflux - December 10, 2014

A Google representative said Penguin now updates continuously, moving away from infrequent, major updates.  This seems to fit ongoing flux after Penguin 3.0's release.

Google Says Penguin To Shift To "Continuous Updates" (SEL)

Pirate - October 22, 2014

Google is reported to have rolled out an update to their Pirate update which was last seen in 2012.

Pirate Update - Search Engine Land

Penguin 2.2 - October 17, 2014

Google announced that a Penguin refresh has taken place, with it set to be a long, worldwide roll out.

Panda 4.1 - September 23, 2014

Google announced a significant Panda update, which included an algorithmic component.  They estimated the impact at 3-5% of queries affect.  Given the "slow rollout" the exact timing was unclear.

Further Reading:
Panda Update - Search Engine Land
Panda 4.1 Analysis and Findings - hmtweb

Authorship Removed - August 28, 2014

Following up on the June 28th drop of authorship photo's, Google announced that they would be completely removing authorship markup (and would no longer process it).  By the next morning, authorship bylines had disappeared from all SERPs.

Further Reading: Authorship Removed - John Mueller.

Mini Panda/SSL Update - August 6, 2014

After months of speculation, Google announced that they would be giving preference to secure sites, and that adding encryption would provide a "lightweight" rankings boost.  They stressed that this boost would start out small, but implied it might increase if the change proved to be positive.

Further reading: HTTPS as a Ranking Signal - Google

Video about Panda Update:

Local Search Update - July 28, 2014

Google updated local search in the US.

Further reading: Experts Weigh Googles Pigeon Local Algorithm Update - Search Engine Land

Modern Devices Update - July 14, 2014

Google are now promoting modern websites for modern devices in Google search results.  This could be a game changer for older websites.

Further reading: Promoting Modern Websites for Modern Devices

Right to be Forgotten - July 2, 2014

Google started removing posts from their search results in the EU for particular queries after a recent EU ruling.

Further Reading: Legal Right to be Forgotten - Search Engine Land

Authorship Profile Photos Removed - June 28, 2014

John Mueller announced on the 25th June that they were going to remove the profile photo from the SERPs, this seems to have taken place on the 28th June.

Further Reading: John Mueller's comment in Google+ - John Mueller

Payday Loan 3.0 - June 12, 2014

Matt Cutts announced at SMX Advanced that they would be launching the Payday 3.0 update.

Further Reading: Google Launching Payday Loan Algorithm 3.0 Targeting Spammy Queries - Search Engine Land

Panda 4.0 - May 19, 2014

A new Panda update was released and a lot of sites were affected (both positively and negatively), Ebay being one of the sites hit massively by this update.

Payday Loan 2.0 - May 16, 2014

Unnatural Link Warning - March 1, 2014

March saw more unnatural link warnings hitting websites.

Page Layout Update 3.0 - February 6, 2014

The page layout update was created to target websites which had a large number of adverts above the fold.

Further Reading: Matt Cutts, Google, Tweeter Comment

Unnatural Link Warning - January 1, 2014

In January a number of sites received a site wide penalty, knocking them out for their brand name.

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