Every time Google updates its algorithm, the organic visibility of millions of sites can change within hours. Knowing when an update started, how long it lasted and what type it was is the first step to interpreting a traffic movement instead of just enduring it.
This timeline collects every algorithm update officially confirmed by Google: core updates, spam updates, reviews updates, helpful content updates and the updates dedicated to Discover. For each one you get the rollout start date, the declared duration and an explanation of what it means for those who live by content and search.
Core updates redefine, at scale, how Google assesses quality: they produce wide, cross-cutting swings without targeting a specific violation. Spam updates instead act on the anti-abuse systems and concern pages that breach the guidelines. Reading the timeline through this lens helps distinguish a drop caused by the algorithm from a problem on your own site: it is the same question answered, in real time, by our SERP volatility index.