The makeheaders program is a simple utility that will automatically generate all ".h" files for large programming project based on information gleaned from the ".c" and/or ".cpp" source files. It operates by scanning the C and/or C++ source code, extracting appropriate macros, structure and subroutine declarations and writing this declarations, in the correct order, into the generated header files.

The makeheaders program has been used on a variety of projects since 1993. It has proven very helpful in reducing the complexing and improving the reliability of these projects. It is very fast and very easy to use, requiring almost no changes to the coding styles employed by most C or C++ programmers.

Since 2007, makeheaders has been used by the Fossil Version Control System. The makeheaders source code (a single file of generic C code) and documentation are now maintained as part of the Fossil project itself.