Binary compatibility enables a single compiled binary to operate correctly on multiple instances of an operating environment that share a common hardware architecture (whether that architecture support is implemented in native hardware or a virtualization layer), but a different underlying software architecture.

Binary compatibility is defined by an Application Binary Interface (ABI). The ABI is a set of runtime conventions adhered to by all tools which deal with a compiled binary representation of a program. Examples of such tools include compilers, linkers, runtime libraries, and the operating system itself. The ABI includes not only the binary file formats, but also the semantics of library functions which are used by applications.