What is File Extension KLF? KaloMa Data files were originally developed by Frank Böpple for the KaloMa software application. How to open KLF files. KLF file is a KaloMa Data File. Learn here what the KLF file is, and what program you need to open or convert the KLF file. The klf file extension is associated with the KaloMa, a calories management software for Microsoft Windows operating system.