Every time Google announces an update, someone asks how long it will take. The answer is usually given as a range somebody remembers, and it is usually wrong for the update in front of you, because core updates and spam updates behave nothing like each other.
Google publishes the exact figures. The Search Status Dashboard records a start date and a duration for every ranking incident, down to the hour. I sat down and tabulated the last ten. Here is what the record actually says.
The numbers
Core updates cluster. Spam updates do not.
The five core updates in that window ran 11 days 21 hours, 12 days 4 hours, 13 days 21 hours, 16 days 18 hours and 18 days 2 hours. That is a tight band. Two weeks is a genuinely useful expectation for a core update, and the two most recent ones came in under it.
The four spam updates ran 19 hours 30 minutes, 2 days 1 hour, 2 days 16 hours and 26 days 15 hours. There is no average worth quoting there. Three of them were over in a weekend and one took nearly four weeks. If someone tells you a spam update takes about a week, they have taken the mean of numbers that should never have been averaged.
The February 2026 Discover update is the odd one out at 21 days 17 hours, and it is a different system again, so it belongs in the table as context rather than as a data point about Search.
There is also a mild trend in the core updates worth naming carefully. The three 2025 core updates averaged a little over 16 days; the two in 2026 came in around 12. Two data points is not a trend, and I would not plan around rollouts continuing to get shorter. It is enough to say the recent ones have been at the fast end of the band, not enough to say anything about the next one.
Why the duration matters more than it sounds
The practical use of these numbers is knowing when your data means anything, and that is a longer wait than the rollout itself.
The rollout window is when rankings are moving. Positions during it are not a result, they are a snapshot of an unfinished process, and a site can drop in week one and recover before the update finishes. Reading day-three data as an outcome is how people end up rewriting pages in response to something that had not happened yet.
Then add reporting lag on top. Search Console performance data is not live, and the last couple of days are still settling when you look at them, which I went through in why Search Console data is delayed. So a core update that ran 12 days is not assessable at day 12. It is assessable a few days after that, when the final stretch of the window has finished landing in your reports.
The workable rule: rollout duration plus roughly three days, then look. For the August 2026 spam update that meant waiting until about 24 August for a rollout that started on 18 August and finished on 21 August, which is what I did before writing anything about it in the August 2026 spam update.
What to do inside the window
Very little, deliberately.
Note the start date from the dashboard rather than from an article, because the dashboard is the source everyone else is quoting and it is more precise than the coverage. Take a baseline of your top pages before the drift starts. Then leave the site alone until the window closes.
The thing not to do is ship changes during the rollout. If you edit pages while rankings are moving for reasons outside your control, you have destroyed your own ability to attribute anything afterwards. You will not know whether the recovery came from your work or from the update finishing, and you will carry that unresolved question into the next update. The full version of that argument, and the checks I run instead, are in what to do during a Google update.
One caveat on the dashboard itself. It records when Google says a rollout started and finished, not when your particular site felt it. Individual sites move at different points inside the window, and some move after it closes. The dashboard tells you the shape of the window, and that is genuinely all it tells you. It is still the only figure in this whole discussion that is not somebody’s recollection.
Sources
- Google Search Status Dashboard, Ranking incident history, for every start date and duration quoted above, read 29 August 2026
- Google Search Central, Google Search updates, on how ranking updates are announced and what a rollout window means
- Google Search Central, debugging search traffic drops, on assessing a change after a rollout rather than during it
- Google Search Console Help, Performance report, for data freshness in the report