Open Search Serverless - How to estimate Search and Query OCUs?

Hello, Search and Indexing OCU utilization/requirement will depend on multiple factors thus, you should test it out with your actual workload to arrive at a rough estimate.

You can monitor the SearchOCU and IndexingOCU account-level CloudWatch metrics to understand how your collections are scaling. You can analyze these metrics to determine your utilization and plug in those metrics in the AWS Pricing Calculator to get a rough estimate.

To better understand scaling, cost and other concerns please go through the documentation available here.