S3-Compatible

S3-compatible describes storage services that implement the HTTP API of the dominant object storage protocol: the same authentication style, request signatures, and operations (put, get, list, delete, multipart upload) so that existing tools and SDKs work unmodified.

Compatibility is a spectrum. Most implementations cover the core object operations that 95% of tools use, but differ on advanced features — object locking, versioning specifics, lifecycle rule syntax, or event notifications. Certification programs exist, but in practice testing your actual toolchain matters more than a badge.

The practical benefit is portability of tooling, not of data: moving terabytes between providers still costs egress on the source side. Choose compatible storage to avoid rewriting backup scripts and CI pipelines, and verify the specific API operations your stack relies on before committing.