YouTube uses a complex algorithm to rank videos and determine their placement in search results, recommendations, and suggested videos. While the exact details of YouTube's algorithm are not publicly disclosed, here are some key factors that are believed to influence video rankings:

Relevance: YouTube aims to show videos that are most relevant to a user's search query or viewing history. The title, description, and tags of a video play a significant role in determining its relevance. Using keywords related to the video's content helps YouTube understand what the video is about.

Engagement: YouTube considers user engagement signals to determine the quality and popularity of a video. Factors such as watch time, likes, comments, shares, and subscriber growth are important indicators of engagement. Videos that generate higher levels of interaction and longer watch times are typically favored by the algorithm.

Watch time and session duration: YouTube values watch time, which refers to the total time users spend watching a video. Videos that keep viewers engaged and lead to longer watch sessions on the platform are generally prioritized. Encouraging viewers to watch the video until the end can positively impact its ranking.

Click-through rate (CTR): The CTR is the percentage of users who click on a video after seeing it in search results or recommendations. Higher CTRs suggest that a video is appealing to users, and YouTube may give it more visibility as a result. Creating compelling titles, thumbnails, and descriptions can help improve CTR.

Video performance: The initial performance of a video, such as the number of views it receives shortly after upload, can influence its ranking. YouTube assesses how quickly a video gains traction and popularity, which can affect its visibility in search and recommendations.

User preferences and history: YouTube takes into account a user's viewing history, subscriptions, and preferences to personalize recommendations. It considers the type of content users typically engage with and tailors suggestions based on their interests and behavior.

It's important to note that YouTube's algorithm continuously evolves, and the specific weightings and factors may change over time. YouTube also provides creators with tools and analytics, such as YouTube Analytics and YouTube Studio, to track video performance, audience engagement, and demographic data. These tools can offer insights into how videos are performing and help creators optimize their content strategy.