Amazon S3, also known as Amazon Simple Storage Service is a data storage and retrieval service from Amazon Web Services. The web based object storage service can be easily scaled up or down to meet demand, an inherent strength of a cloud based service.

According to Amazon S3 offers 99.999999999% durability because it automatically creates and stores copies of data across multiple systems. Since S3 is a cloud storage service, the total volume of data and number of objects that can be stored is unlimited.

AWS uses the simple key-based storage principle to organize data. When data is stored, a unique object key is assigned to it, which is used later to retrieve that data. Object tagging can also be used to organize data.

S3 customers can select from six different storage classes based on their frequency of usage, access patterns, volume and the expected life of data. The storage classes are the following:

S3 Standard: Best for frequently accessed data. Delivers low latency, high throughput. Offers 99.99% availability over a given year.

S3 Intelligent-Tiering: Designed to save costs by automatically moving data to the most cost-effective tier, this storage class if ideal for data with unknown and changing access priorities. For a small fee, AWS will monitor access patterns and moves objects that is not accessed for the last thirty days to an infrequent access tier. If the object in the infrequent tier is accessed, it is automatically moved to the frequent access tier. 

S3 Standard-IA: This low-cost, high-performance storage class is great for data that are accessed less frequently, but needs quick access when required. Ideal for long term storage, backups and to store disaster recovery files. 

S3 One Zone-IA: This storage service is similar to Standard-IA, but offers reduced availability, thereby reducing the cost. Unlike other storage services that remain available from three different available zones by default, One Zone-IA keeps data in a single availability zone. 

S3 Glacier: This service is mainly used for data archiving. According to AWS customers can store data in Glacier “at costs that are competitive with or cheaper than on-premises solutions.” Data can be retrieved using three options, ranging from minutes to hours. Expedited retrievals return data in one to five minutes, Standard retrievals can be done in three to five hours and Bulk retrieval returns data in five to twelve hours.  

S3 Glacier Deep Archive: This is Amazon’s lowest-cost storage service, designed for data storage needs for seven to ten years or even longer. Data gets stored in at least three geographically-dispersed availability zones and can be typically restored within 12 hours. 


Performance Comparison of S3 Storage Classes

All storage classes offer 99.999999999% durability, Object storage and life-cycle transitions.

Storage ClassS3 StandardS3 Intelligent-Tiering*S3 Standard-IAS3 One Zone-IA†S3 GlacierS3 Glacier Deep Archive
Availability99.99%99.90%99.90%99.50%N/AN/A
Availability SLA99.90%99%99%99%N/AN/A
Availability Zones≥3≥3≥31≥3≥3
Minimum capacity charge per objectN/AN/A128KB128KB40KB40KB
Minimum storage duration chargeN/A30 days30 days30 days90 days180 days
Retrieval feeN/AN/Aper GB retrievedper GB retrievedper GB retrievedper GB retrieved
First byte latencymillisecondsmillsecondsmillisecondsmillisecondsminutes or hourshours

Amazon S3 Pricing:

Similar to other cloud services from AWS, there is no minimum payment or long term commitment required to use Amazon S3. The pay as you go model allows customers to pay only for the resources they consume in a given month. Price differs based on storage location.

Example: S3 Storage Pricing in US East (Ohio)

Storage ClassFirst 50 TBNext 450 TBOver 500 TB 
S3 Standard Storage$0.023 per GB$0.022 per GB$0.021 per GB
Storage ClassAll Storage/Month
S3 Standard-IA$0.0125 per GB
S3 One Zone-IA$0.0100 per GB
S3 Glacier $0.0040 per GB

Apart from storage, customers also pay for data retrieval, storage management, data transfer, replication and few other services. For more details on S3 storage pricing please visit AWS