What is SFV file?

The .sfv file extension is usually used for SFV files. SFV is used to verify that a file has not been corrupted, but does not otherwise verify its authenticity. Despite the weaknesses of the SFV format, it is popular due to the relatively small amount of time taken by SFV utilities to calculate the CRC32 checksums when compared to the time taken to calculate cryptographic hashes such as MD5 or SHA-1.

SFV uses a plain text file containing one line for each file and its checksum in the format FILENAMECHECKSUM. Any line starting with a semicolon ';' is considered to be a comment and is ignored for the purposes of file verification. The delimiter between the filename and checksum is always one or several spaces; tabs are never used. A sample SFV file is:

file_one.zip c45ad668

file_two.zip 7903b8e6

file_three.zip e99a65fb