Amazon Simple Storage Service

A representative AWS storage service for storing files securely and at low cost.

An object storage service. Stores HTML, images, logs, backups, static site files, and more.

• Hosting files for static websites
• Storing images, PDFs, and logs
• Backups and data lakes

• An object storage service
• Provides high durability
• Optimizes costs with storage classes and lifecycle rules

• Combine with CloudFront when distributing static sites
• Do not expose S3 directly; control access with OAC or bucket policies
• Choose Standard, IA, or Glacier tiers based on use case

Amazon Simple Storage Service (Amazon S3) is an object storage service provided by AWS. It stores files (objects) in buckets (bucket names are globally unique across AWS) and can hold any kind of data, including HTML, CSS, JavaScript, images, videos, logs, backups, and data lake files. The standard Amazon S3 Standard class provides 99.999999999% (eleven nines) of object durability, with redundant storage across multiple AZs built in. Major storage classes include S3 Standard for frequently accessed data, S3 Standard-IA (Infrequent Access) and S3 One Zone-IA for infrequently accessed data, S3 Intelligent-Tiering for data with unknown access patterns, and S3 Glacier Instant Retrieval, S3 Glacier Flexible Retrieval, and S3 Glacier Deep Archive for archival storage. By configuring lifecycle policies, objects can be automatically transitioned to cheaper classes after a set period or deleted once no longer needed. Typical use cases include static website delivery combined with CloudFront, long-term storage of logs, backups, and snapshots, data lake foundations integrated with Amazon Athena, Amazon EMR, and Amazon Redshift Spectrum, and serving as the output destination for various AWS services (CloudTrail, VPC Flow Logs, ELB access logs, and others). Pricing is composed of storage capacity multiplied by the storage class rate, request counts, data transfer volume, and lifecycle transition request counts. From a security perspective, Block Public Access is enabled by default, providing protection against unintended public exposure. When serving content through CloudFront, the recommended configuration uses Origin Access Control (OAC) to restrict direct access to the bucket.

• Amazon S3 User Guide (AWS Official Documentation)
• Amazon S3 (AWS Official)

Last updated: 2026-06-01