s3cmd

A command‑line client written in Python that interacts with Amazon S3 and any storage service that implements the S3 API, such as Google Cloud Storage or DreamHost DreamObjects. It supports uploading, downloading, listing, and managing objects and buckets, and can be used in scripts, cron jobs, or other automated workflows. The tool is licensed under GPL v2 and runs on Python 2.6+ and Python 3+.

Power users can leverage more than sixty options, including multipart uploads, server‑side encryption, incremental backups, synchronization of local directories with buckets, ACL and metadata handling, and bucket‑policy management. These features make it suitable for batch processing, automated backups, and detailed control of storage resources without a graphical interface.

The client requires only the user’s AWS access and secret keys for authentication, and all charges are incurred directly from Amazon S3 usage. It is distributed as free, open‑source software for both commercial and private projects.