Something shifted this week. After a stretch of quiet in Google rankings, sudden movement was spotted starting Monday, May 12. It continued into Tuesday and then flared again on Thursday, May 16. These were not minor tremors. SEO tools lit up. So did community chatter.
The last confirmed update from Google was the March 2025 Core Update. Since then, nothing official has been announced. But SERP tracking tools like Semrush Sensor and Mozcast showed sharp spikes this week. Traffic patterns across various sites—especially affiliate, health, and content-heavy domains—shifted quickly.
Earlier hints of volatility showed up on May 8, but they were smaller. What we saw on the 12th and 13th looked different. Higher. Broader. Unconfirmed but visible.
Across forums and tracking threads, webmasters described it clearly:
- “All traffic is gone. Just a few clicks in the past 24 hours.”
- “One site doubled overnight. Never seen this before.”
- “Mobile pages took a hit. Desktop is stable.”
These are not isolated glitches. Some tools picked it up. Others missed it. The inconsistency suggests this might be targeted testing, not a full algorithm rollout.
What SEO Tools Detected on May 8, 12, 13, and 16, 2025
Here is how top SEO tracking tools reacted during the recent Google ranking changes. These tools help track shifts in search results and give us a good idea when something big is happening in the algorithm. When they show high activity, it often means something has changed in the Google algorithm.
Below is a clear day-by-day snapshot from the tools:
| Date | Semrush Sensor | MozCast | RankRanger |
| May 8 | Very High | Moderate | Low |
| May 12 | Moderate | High | Moderate |
| May 13 | Moderate | Very High | High |
| May 16 | Very High | High | Moderate |
On May 12, SEO tools like Semrush Sensor and MozCast reported high volatility, indicating significant fluctuations in search rankings. The situation intensified on May 13, with both tools showing very high volatility levels. RankRanger also noted high fluctuations on this day. By May 16, the volatility had moderated, but MozCast still reported high activity, suggesting ongoing adjustments in Google’s search algorithm.
These fluctuations were observed across various industries, including health, finance, and e-commerce, affecting both desktop and mobile search results.
Note: The above data is based on general trends reported by the mentioned SEO tools during the specified dates.
May 8: First Signs of Movement Return
May 8 felt different. After two quiet weeks, some tools started picking up light ranking shifts. Semrush Sensor and MozCast both showed a moderate rise. RankRanger showed low signals but still moved slightly.
At the same time, many SEOs began noticing traffic dips or gains. Forum posts described changes across blog pages, service sites, and affiliate pages. While not every site was affected, the pattern was clear. Movement had started again.
There was also a GA4 real-time bug that morning. Some users saw gaps in live reporting, which made it harder to confirm what was real and what was not. But tool data and SEO chatter both pointed to early activity.
May 12: Rankings Start to Shift Wider
After a relatively calm period following the March 2025 core update, May 12 marked the onset of notable fluctuations in Google’s search rankings. SEO tracking tools such as Semrush Sensor and MozCast reported significant volatility, indicating substantial changes in search result positions. RankRanger also detected increased activity, though to a slightly lesser extent.
The SEO community corroborated these findings, with professionals noting unusual traffic patterns and ranking shifts across various industries. These observations align with reports from authoritative sources, confirming the heightened volatility during this period.
Google Search ranking volatility on May 8th https://t.co/UE1LrwebUC pic.twitter.com/VlSnglbWtn
— Barry Schwartz (@rustybrick) May 8, 2025
May 13: Volatility Hits Its Peak
On May 13, 2025, significant fluctuations in Google Search rankings were observed, as reported by SEO tracking tools and community discussions. Semrush Sensor and MozCast indicated very high volatility, suggesting substantial changes in search result positions. RankRanger also detected increased activity, though to a slightly lesser extent.
The SEO community corroborated these findings, with professionals noting unusual traffic patterns and ranking shifts across various industries. These observations align with reports from authoritative sources, confirming the heightened volatility during this period.
Google Search Ranking Volatility Spiked Thursday – May 12 & 13 https://t.co/BTOnjLTA4S Google Search may be pushing out another search ranking update of sorts, I am seeing more signs of tremors and volatility over the past 24-hours. Some of the tools are already picking up on i…
— Pistakkio – SEO, SEA, SEM & PPC 🇺🇦 (@pistakkiomktg) May 13, 2025
For a detailed analysis and community insights, refer to the article by Barry Schwartz on Search Engine Roundtable: Google Search Ranking Volatility May 12-13.
May 16: Search Rankings Shift Again Across Categories
Friday, May 16 showed strong ranking activity. After the spike seen earlier in the week, Semrush Sensor recorded a score of 9.2, marking the day as very high volatility. This level of movement often lines up with Google testing or pushing new changes live.
Several industries felt the shift. Categories like Finance, News, Food and Drink, and Business each showed volatility scores of 9.4, the highest on the list. Other sectors, including Real Estate, Reference, and Health, also saw impact, though at slightly lower levels.
SERP features also moved. The appearance of video results jumped by over 5 percent, while AI Overview and People Also Ask dropped sharply. This kind of shift usually means Google is rebalancing how it serves search formats.
Some SEOs saw traffic swings again. A few sites gained visibility. Others dropped across mobile searches. There was no official announcement from Google, but patterns point to something active behind the scenes.
What SEOs Are Saying
The SEO community has been actively discussing the recent fluctuations in Google Search rankings. Here are some notable observations:
“Ranking has plummeted, and Google traffic is 0 so far… So it goes.”
— WebmasterWorld“Some tools are reporting even more heated volatility as of May 9th. SEOs are seeing heavily localized SERPs, making it tough for tools to reliably track positions.”
“From 4 to 10 May, my rankings improved a lot, before continually deteriorating until today.”
“Traffic is terribly bad even on Saturdays and Sundays these days, it’s so upsetting.”
— WebmasterWorld
Final Takeaway from the May 2025 Ranking Shifts
These shifts may not be part of a confirmed core update, but the volatility is real. Ranking movements were clear across four separate dates — May 8, 12, 13, and 16. Tools picked them up. So did site owners.
There has been no official statement from Google. But the pattern of fluctuations matches previous moments we have seen before major updates. Similar waves were recorded during March 2024, September 2023, and before that in May 2022.
This time, the changes seemed to roll out in waves rather than all at once. First signs on May 8, major shakeups on the 12th and 13th, and continued tweaks into the 16th. Some sites dropped sharply. Others saw gains that did not last.
