The SFV or “Simple File Verification” file extension is most commonly used in burning data to optical media, or used in conjunction with files downloaded from the internet. It is commonly found in a compressed archive such as ZIP or RAR file, used to validate the integrity of the files contained in the archive. This kind of file extension stores plain text checksum data for a file, folder, or disk, which indicates what data it contains, can be used to check for corrupt files, missing files, or files of the wrong size.
SFV files have CRC32 (Cyclic Redundancy Check) checksum for each file in the archive calculated using the original file size, which is a 32-bit integer. The archive can be assumed as corrupt if the checksum of any of the files in the archive do not match those specified in the SFV file, and this may be due because a file in the archive is missing or mainly due to incomplete transmission.
Though it can verify whether or not a file is incomplete or missing, it shouldn’t be used to determine the genuineness of the file because it is possible to modify the contents even as still retaining the same checksum. Since SFV file are only suitable for relatively small file, this means that different files could possibly generate the same checksum. Examples for larger files would be the ISO images, MD5 hashes are more usually used as they support 128-bit value.
SFV files can be opened using any Simple File Verification application, and using these applications will result in the associated files having checksum calculated. Below is the list of these applications:
| Mac OS | SuperSFVMacSFV |
| Windows | QuickSFVMooSFV
RapidCRC Traction SFV Checker SlavaSoft FSUM pure-sfv WinSFV |
| Linux | QuickSFVCheck SFV
pure-sfv |
