Rohan Paul (@rohanpaul_ai) · 10/20/2026, 13:45:16
X Updates Recommendation Algorithm to Prioritize Dwell Time and Completion
X has implemented two key algorithmic changes to its 'For You' feed, aiming to maximize user dwell time. The new ranking model better predicts probable time spent, while the retrieval model prioritizes posts users are likely to read completely. This shift restructures how content from non-followed accounts is filtered and coincides with a significant growth in daily active seconds to approximately 500 billion.
SOURCE COVERAGEFull Original Report
Rohan Paul (@rohanpaul_ai) · 2026-10-20 05
X has changed 2 stages of its For You feed to favor time spent and posts people finish.
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Musk said the new ranking model “predicts probable time spent much better”
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Dwell time was already among the ranker’s predicted actions before this update, which means the new model sharpens an existing objective.
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The second change acts earlier, at retrieval, which turns you and each post into vectors and pulls the nearest ones from accounts you don’t follow. Posts from accounts you follow arrive through a separate system, so this retrieval model mainly decides which posts from accounts you don’t follow make the shortlist.
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Musk said this step is now trained on read-through, so it learns to pick posts that people tend to read to the end. A post that people usually abandon halfway is therefore less likely to make the shortlist.
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daily user active seconds is seeing quite a massive growth, 2026 climbs from roughly 410B a day in mid-August to about 500B by mid-October,
↳ 引用 @elonmusk (Elon Musk): Two important changes to timeline recommendations:
New AI/SI ranking model that predicts probable time spent much better
Retrieval model trained to surface posts people read all the way through
User active seconds is growing exponentially and hitting all-time highs almost every day:
