S3 Backup FAQ

General Topics

What is Amazon S3?

S3 is an acronym for Simple Storage Service. Amazon describes S3 this way:

Amazon S3 provides a simple web services interface that can be used to store and retrieve any amount of data, at any time, from anywhere on the web. It gives any developer access to the same highly scalable, reliable, fast, inexpensive data storage infrastructure that Amazon uses to run its own global network of web sites. The service aims to maximize benefits of scale and to pass those benefits on to developers.

The service itself is not accessible directly; it provides a low-level API that developers can use to build applications that use online data storage, like S3 Backup.

What is S3 Backup?

S3 Backup is a desktop application that makes it trivial for everyone to use Amazon’s infrastructure for remote backups and secure online file storage.

It features very strong encryption, compression, easy access to your backed up files and backup scheduling built in.

This tool was launched just months after the initial Amazon S3 announcement back in 2006 and is arguably the most mature on the market.


How much does it cost?

S3 Backup license for lifetime use costs 35 USD for personal use and 75 USD for use on the server.

Storage fees are collected separately by Amazon.

Is there a free trial?

You can use S3 Backup with a trial license for 60 days.

What the purchasing process looks like?

The process of getting a license is designed to take as few steps as possible. When you order a license it’s immediately bound to your email, so when you log into your online account, you can immediately see it and assign to a computer.

We offer a 30 days money-back guarantee.

Which license type do I need?

If you want to use S3 Backup on a personal computer, you need to get a personal license. This license is good for Windows XP, Windows 7 and other consumer Operating Systems.

If you will be using S3 Backup to back up a server, you will need a server license.

What’s the licensing model?

Every license is a non-expiring, reusable permission to use the app on a certain computer. If you upgrade a computer, you can transfer the license to the new one without paying anything extra.

Can I use S3 Backup for corporate backup?


For orders starting from 5 personal or 3 server licenses we offer volume discounts.


Where and how my data are stored?

When you use S3 Backup the application communicates directly with Amazon servers.

How reliable is this storage? What if a natural disaster occurs?

Amazon uses multiple geo-distributed datacenters and your data are replicated through the system. This means that even if one of the datacenters will be swept from the surface of Earth by a tornado your data would still be intact. This is something no other remote backup solution can offer.

Remember, S3 is a system that Amazon, a Fortune 500 company, uses to run its own business-critical operations, which should give you some confidence about the durability of your data.

Security and Encryption

I need to back up sensitive information. Who can access my data?

When you use S3 Backup you don’t have to worry about people who manage the servers. S3 Backup has an option to encrypt all your data with AES-256. It’s is a heavily tested 256bit cipher accepted by NIST in 2001 after a 5-year standardization process. It was approved by NSA for protection of US Government TOP SECRET information.

The result is that your data are absolutely secure — not just hackers, even datacenter operators or Government can’t decrypt your data, not even if they wanted to.

We have a detailed blog post on all the technical details of the encryption pipeline we use.

I can’t trust other users of my computer; can they access my online storage?

No, they can’t if you have selected to protect your account with a password. It’s as easy as clicking a checkbox and your credentials are encrypted with Blowfish. If someone doesn’t know your password, he won’t be able even to see a remote file listing, period.

If the untrusted party doesn’t have administrative privileges on that machine, you don’t even need to use a password — account configuration is stored in a user-specific location accessible only to you and local admins.

What is the storage format used?

See a page on stream codecs for more info.

Errors and Connectivity

How error-proof is Amazon S3?

Errors can sometimes happen, it’s a normal occurrence in any complex system and the client software should be able to intelligently handle it. S3 Backup uses a smart retry algorithm to make sure every operation ultimately succeeds without any user interaction.

Every operation is atomic and with the retry logic in place data will not get corrupted.

How does S3 Backup handle connection errors? (For ex. when uploading on a flaky connection.)

While uploading, connection errors are handled the same way servers errors are — by retrying with exponential falloff — in 0, 5, 10 seconds etc.

I want to know of every request that S3 Backup sends to Amazon.

You can, just pop up debug log, it’s in the menu under Help → Show debug log (Ctrl+L). It reports all requests sent to Amazon and other detailed information that could be of interest to the more technical users of this software. This console will also pop up when the application issues a warning (for ex. when retrying a request) or an error.

If you have any questions that were not answered here, feel free to ask us.