Google Algorithm Sensor documentation
The Google Algorithm Sensor answers one question quickly: is Google rolling out an update right now? It is built only on what Google itself confirms, and it includes every confirmed update since 2011.
Open the Google Algorithm Sensor
What it does
- The algorithm weather: a level from 1 to 10, from Calm to Stormy.
- Any update rolling out now, with the day of the rollout and its rough progress.
- Days since the last core update, spam update and any update.
- How many updates Google released in the last 12 months, and the average gap between core updates.
- The full history of confirmed updates, filterable by type and year.
The weather levels
| Level | Weather | When |
|---|---|---|
| 9 | Stormy | A core update is rolling out |
| 7 | Windy | A helpful content or reviews update is rolling out |
| 6 | Windy | A spam or link spam update is rolling out |
| 5 | Unsettled | Another kind of update is rolling out |
| 5 | Settling | A core update finished in the last 14 days |
| 4 | Settling | Another update finished in the last 14 days |
| 2 | Calm | No update is active or recent |
Progress during a rollout is the day of the rollout compared with a typical length: about 14 days for core updates and 7 for spam updates, capped at 95 percent until Google marks it complete.
Where the data comes from
The sensor reads Google's Search Status Dashboard, where Google posts each ranking update when it starts and marks it complete when it ends. The server checks the dashboard's feed at most every three hours and keeps the last good copy if the feed is unavailable.
Updates before November 2021, when the dashboard began, come from Google's own announcements on Search Central, including Panda, Penguin, Hummingbird, the HTTPS, mobile-friendly, speed and page experience updates, Medic and BERT, plus three announced changes from 2024: INP joining Core Web Vitals and the site reputation abuse policy.
The sensor does not scrape Google's search results. That would break Google's terms of service, and it would add guesswork. Every status you see is based on what Google has confirmed.
Tips for using it
- Wait until a rollout is complete, then give rankings one to two weeks to settle before you judge the result.
- Compare like with like: the same weekdays, before and after.
- Look at which pages moved. Core updates reassess pages, not only whole sites.
- When the sensor is calm and your numbers change, check your own site changes, competitors and tracking first.
- Run the Google Update Risk Checker to see how exposed your site is to each type of update.
Limits
- Google makes many smaller changes it does not announce, and these do not appear in the sensor.
- Rollout progress is an estimate from typical rollout lengths. Only Google's dashboard can say when an update is complete.
- It is an independent tool, not made by or affiliated with Google.