Alibaba Cloud Object Storage Service (OSS) is a secure, cost-effective, and highly reliable cloud storage service that allows you to store a large amount of data. OSS is designed to provide 99.9999999999% (twelve 9's) data durability and 99.995% data availability. OSS provides multiple storage classes to help you manage and reduce storage costs.

OSS supports RESTful API operations that are independent of the OSS console. You can store and access data from all applications anytime and anywhere.

You can call API operations and use SDKs or OSS migration tools provided by Alibaba Cloud to transfer large amounts of data to and from Alibaba Cloud OSS. You can use OSS buckets of the Standard storage class to store image, audio, and video objects for apps and websites. You can use OSS buckets of the Infrequent Access (IA), Archive, or Cold Archive storage class to store infrequently accessed objects at a low cost and with longer storage period.

Get started with OSS

  • Video tutorial

    The following video quickly guides you through OSS.

  • FAQ

    For frequently asked questions about OSS, see FAQ.

  • Learning path

    OSS Learning Path helps you get started with OSS. You can learn basic OSS operations, and then perform secondary development by using a variety of API operations, SDKs, and convenient tools.


  • storage class

    The storage class of a bucket or an object. OSS provides the following storage classes to cover a variety of data storage scenarios from hot data to cold data: Standard, IA, Archive, and Cold Archive. The Standard storage class provides high-durability, high-availability, and high-performance object storage services that can support frequent data access. The IA storage class is suitable for storing data that is accessed once or twice a month. In addition, the unit price of IA storage is lower than that of Standard storage. The Archive storage class is suitable for storing archive data for at least six months. The Cold Archive storage class is suitable for storing cold data over a long period of time. For more information about storage classes, see Overview.

  • bucket

    A container used to store objects in OSS. All objects are contained in buckets. You can configure a variety of bucket attributes such as the region, access control list (ACL), and storage class. You can create buckets of different storage classes to store your data.

  • object

    The basic unit used to store data in OSS. Objects are also known as files. An object consists of object metadata, object data, and an object key. The key of an object uniquely identifies the object in a bucket. Object metadata consists of key-value pairs that describe object attributes, such as the last modified time and the size of the object. You can also specify the user metadata of an object.

  • region

    The physical location of an OSS data center. You can select a region to create a bucket based on the cost and location of the requests to the bucket. For more information, see Regions and endpoints.

  • endpoint

    The domain name that is used to access OSS. OSS uses RESTful API operations to provide services. Different regions are accessed by using different endpoints. Access over the internal network or over the Internet within the same region also uses different endpoints. For more information, see Regions and endpoints.

  • AccessKey pair

    The access credential that is used to authenticate a requester. An AccessKey pair consists of an AccessKey ID and an AccessKey secret. OSS uses symmetric encryption based on AccessKey pairs to verify the identity of a requester. The AccessKey ID is used to identify a user. The AccessKey secret is used to encrypt and verify signature strings. The AccessKey secret must be kept confidential. For more information about how to obtain an AccessKey pair, see Obtain an AccessKey pair.

Common operations

  • Create buckets

    Before you can upload objects to OSS, you must create a bucket. You can configure various attributes such as the region, ACL, and other metadata for a bucket. For more information about how to create a bucket, see Create buckets.

  • Upload objects

    After you create a bucket, you can upload objects of different sizes to the bucket. For more information about how to upload objects, see Upload objects.

  • Download objects

    After you upload objects to a bucket, you can download the objects to the default download path of your browser or the specified local path. For more information about how to download objects, see Download objects.

  • List objects

    You can list all objects in a bucket. If a large number of objects are stored in a bucket, you can also list some of the objects in the bucket. For more information about how to list objects, see List objects.

  • Delete objects

    You can manually delete one or more objects that you no longer need. You can also configure lifecycle rules to allow OSS to automatically delete a single object or multiple objects. For more information about how to delete objects, see Delete objects.


  • Versioning

    OSS allows you to configure versioning for a bucket to protect objects that are stored in the bucket. After you enable versioning for a bucket, data that is overwritten or deleted in the bucket is saved as a previous version. You can use versioning to recover a previous version of an object that is accidentally overwritten or deleted. For more information about versioning, see Overview.

  • Bucket Policy

    The owner of a bucket can configure bucket policies to grant users different permissions to access the specified OSS resources in the bucket. For example, you can configure bucket policies to authorize other Alibaba Cloud accounts or anonymous users to access or manage all or some resources in your bucket. You can also configure bucket policies to grant full permissions such as read-only, read/write, or full permissions to different RAM users of the same Alibaba Cloud account. This way, different RAM users have different permissions to access or manage resources in your bucket. For more information about how to configure bucket policies, see Configure bucket policies to authorize other users to access OSS resources.

  • CRR

    Cross-region replication (CRR) provides automatic and asynchronous (near real-time) replication of objects across buckets in different OSS regions. Operations such as creating, overwriting, and deleting objects can be synchronized from a source bucket to a destination bucket. CRR can meet your requirements for cross-region disaster recovery and data replication. For more information about CRR, see CRR.

  • Data encryption

    Server-side encryption: When you upload an object to a bucket for which server-side encryption is enabled, OSS encrypts the object and stores the encrypted object. When you download the encrypted object from OSS, OSS automatically decrypts the object and returns the decrypted object. A header is added in the response to indicate that the object is encrypted on the OSS server. For more information about server-side encryption, see Server-side encryption.

    Client-side encryption: Before you upload an object to a bucket, the object is encrypted on the local client. For more information about client-side encryption, see Client-side encryption.

Manage OSS

You can use a variety of methods to upload objects, download objects, and manage OSS.

  • Manage OSS by using the OSS console

    OSS provides a web-based console. You can log on to the OSS console to manage your OSS resources. For more information, see Use Alibaba Cloud accounts to log on to the OSS console.

  • Manage OSS by using API operations or SDKs

    OSS provides RESTful API operations and SDKs for multiple programming languages to facilitate secondary development. For more information, see List of operations by function and Overview.

  • Manage OSS by using tools

    OSS provides multiple management tools, such as ossbrowser, ossutil, and ossftp. For more information, see OSS tools.

  • Manage OSS by using CSG

    OSS uses a flat structure instead of a hierarchical structure to store objects. All elements are stored as objects in buckets. To use OSS in the same manner in which local file systems are used, you can configure Cloud Storage Gateway (CSG). For more information, visit the CSG product page.


Traditional storage service providers require you to purchase a reserved amount of storage capacity and network traffic before you use resources. If your storage capacity or traffic usage exceeds the reserved amount, your service is deactivated or you are charged excess fees. At the same time, if your storage capacity or traffic usage does not exceed the reserved amount, you are charged for the full amount of the storage and traffic.

OSS charges you only for the storage capacity and traffic that you consume. Therefore, you do not need to purchase storage capacity and traffic before you use resources. You can take the cost advantages of the flexible infrastructure provided by Alibaba Cloud to grow your business.

For more information about OSS pricing, go to the Pricing tab of the OSS product page. For more information about OSS billing methods, see Overview.

Related services

After you upload your data to OSS, you can use other Alibaba Cloud features and services to manage your data.

The following features and services are frequently used with OSS:

  • Image Processing (IMG): a service that allows you to perform a variety of operations such as format converting, resizing, cropping, rotating, and adding watermarks to images stored in OSS. For more information, see IMG implementation modes.
  • Elastic Compute Service (ECS): a cloud computing service that provides elastic and efficient computing capability. For more information, visit the ECS product page.
  • Alibaba Cloud CDN: a distributed network that caches resources from an origin server to edge nodes in different regions to accelerate content delivery. For more information, visit the CDN product page.
  • E-MapReduce (EMR): a big data processing solution built on ECS. EMR is developed based on open source Apache Hadoop and Apache Spark to facilitate data analysis and processing. For more information, visit the E-MapReduce product page.
  • ApsaraVideo Media Processing: a service that converts audio or video objects stored in OSS into files that are suitable for playback on PCs, TVs, and mobile devices. Deep learning results from large amounts of data help ApsaraVideo Media Processing perform multimodal analysis on the audio, text, and images in video files and the content of audio files. ApsaraVideo for Media Processing uses the analysis results to intelligently audit, understand, and edit the content of the audio or video files. For more information, visit the ApsaraVideo Media Processing product page.
  • Data Online Migration: a service that allows you to migrate data from a third-party storage service such as Amazon Web Services (AWS) and Google Cloud to OSS with ease. For more information, see Data Online Migration documentation.
  • Data Transport: a service that helps you migrate large amounts of data from local storage to OSS. For example, you can use Data Transport to migrate terabytes or petabytes of local data to OSS when the local network bandwidth is insufficient and expansion costs are high. For more information, see What is Data Transport?

Alibaba Cloud storage services

In addition to OSS, Alibaba Cloud also provides a variety of storage services such as file storage and block storage for different scenarios. For more information about Alibaba Cloud storage services, see Overview.

For more information about use cases and solutions of Alibaba Cloud storage services, visit the Alibaba Cloud Storage.