You can take backup of s3 using Amazon, other cloud services like google and local system.
S3 Browser comes with a simple Folder Sync Tool allowing you to upload or download only new and changed files and thereby significantly optimize your bandwidth usage and save you time when performing backups to Amazon S3.
This very good tool if your using window. here is the link http://s3browser.com/amazon-s3-folder-sync.aspx
if you using Linux based system then i tired this tool also good one DragonDisk
you can take backup of s3 in google cloud as well.
The gsutil command-line tool also enables you to transfer data between Cloud Storage and other locations. While you can use gsutil to work with Amazon S3 buckets and transfer data from Amazon S3 to Google Cloud Storage, Storage Transfer Service is recommended for this use case.
As with any environments, the best practice is to have a backup and to put in place safeguards against malicious or accidental users errors. For S3 data, that best practice includes secure access permissions, Cross-Region Replication, versioning and a functioning, regularly tested backup.
- How durable is Amazon S3?
Amazon S3 Standard and Standard - IA are designed to provide
99.999999999% durability of objects over a given year. This durability level corresponds to an average annual expected loss of 0.000000001%
of objects. For example, if you store 10,000 objects with Amazon S3,
you can on average expect to incur a loss of a single object once
every 10,000,000 years. In addition, Amazon S3 is designed to sustain
the concurrent loss of data in two facilities.