Amazon Macie
fully managed data security and data privacy service that uses machine learning and pattern matching to discover and protect your sensitive data in AWS.
Pricing
you are charged based on the number of Amazon S3 buckets evaluated for bucket-level security and access controls and the quantity of data processed for sensitive data discovery.
Free tier (sensitive data discovery)
For sensitive data discovery jobs, the first 1 GB processed every month in each account comes at no cost. For each GB processed beyond the first 1 GB, charges will occur.