DataNumen File Splitter is the best FREE tool to split and join your large files. It can also compare files and calculate checksum for files.
Note: DataNumen File Splitter is freeware. You can download, use and re-distribute it freely.
Support to split a large file into small files, based on the specified size limit.
Support join several small files into one large file.
Support to compare two files byte by byte, to check whether the two files are identical to each other.
Support to calculate the MD5 check sum of a file.