Summary of formats supported by the library and command-line tools.
Libarchive is highly modular. It was designed from the beginning to make it relatively easy to add new archive formats and compression algorithms. Note, however, that each program that uses libarchive chooses which formats it wants to use, so support in libarchive does not guarantee support in any particular program. Of course, the bsdtar and bsdcpio programs included in the libarchive distribution do enable all libarchive formats by default.
For developers: Note that libarchive is modularized in such a way that statically-linked executables pay nothing for formats that they don't use. If you choose to omit a particular format, no code for that format will be linked into your program. In particular, you only need zlib, bzlib, or lzma libraries if you specifically enable the corresponding formats. (This is not true if you use dynamic libraries, of course.)
The read pipeline automatically recognizes archives processed with any combination of the following. Libarchive 3.0 supports multiple filters when writing archives.