SERP Volatility
In one line
SERP volatility is a measure of how much rankings are shifting compared with a normal day — usually the first signal teams use to spot a Google algorithm update in flight.
Going deeper
SERP volatility is the 'how shaky are rankings today' score that SEO tool vendors publish — Semrush Sensor, Mozcast, Advanced Web Rankings and so on. Days where the score spikes well above its baseline almost always coincide with a Google algorithm update.
In practice, when your rankings move suddenly, the first thing to check is whether market-wide volatility was high that day. If everyone was shaking, it's most likely an update; if only your site moved, look at recent on-site changes or tech issues first.
AI Overviews now add a second axis. The same query can flip in and out of an AI Overview from day to day, so traffic can wobble even with rankings unchanged — pure 'feature presence' volatility on top of classic position volatility.
Related terms
Google Core Update
A Google Core Update is one of the broad algorithm refreshes Google ships a few times a year — a wide reassessment of site quality and E-E-A-T rather than a fix to a specific issue.
SEOGoogle Algorithm Updates
Google algorithm updates are the recurring algorithm refreshes Google rolls out — Core Updates, Helpful Content Updates, Spam Updates and Reviews Updates being the headline families.
SEOKeyword Ranking
Keyword ranking is the position your page holds for a given query in search results — the most intuitive single metric for tracking SEO progress over time.
GEO·AEOAI Overview
Google AI Overviews is the AI-generated summary that appears above the standard results in Google Search — one of the most prominent zero-click surfaces today.
SEOSERP
SERP (Search Engine Results Page) is the page a search engine returns for a query — now mixing organic links with ads, rich features and AI-generated answers.
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