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

When you are transferring large files or groups of files over the Internet, it is important to make sure that the files do not get corrupted or damaged during the transfer. Simple File Verification files, called SFV files, store a list of data that can be compared to the downloaded files to determine if any of the downloaded files are corrupt, missing or the wrong size. SFV files need a third-party software program to open and reference them.

There are a few nice software applications available that can open an SFV file and run a check on the downloaded archive. For example, QuickSFV is a good choice to open SFV files. The instructions below will guide you through all the steps.

Instructions

Step 1

Download QuickSFV to your computer, then launch the executable and proceed to install QuickSFV.

Step 2

Once your reach the File Associations section, make sure to check the SFV box as pictured below:

Step 3

If all goes well, you should now be able to open any SFV files that may have come bundled with your downloaded archives and check the archive for corruption. Simply browse to and double click the .sfv file to open it with QuickSFV.

SFV, which stands for "Simple File Verification," is a program that checks the files you downloaded and matches them with the files that the creator uploaded. SFV checks the files a person has downloaded to find random corruptions; however, it cannot be used for checking authenticity in any useful way. WinRAR and Quick SFV are both free applications you can download and use to make SFV files.

Instructions

WinRAR

Step 1

Download and install WinRAR.

Step 2

Open the folder containing the files you want to convert to SFV.

Step 3

Select the files with your mouse and right click on them. Then select Create .SFV File.

Step 4

Give the SFV files a name and click OK. When WinRAR has finished creating the file, double click on it to check the original file for corruptions.

QuickSFV

Step 1

Download and install QuickSFV.

Step 2

Open the folder containing the files you want to convert to SFV.

Step 3

Select the files with your mouse and right click on them. Then select Create .SFV File.

Step 4

Type in the full path and name for the SFV file and click OK. After QuickSFV has made the file, right click on it and select Verify All to check the original file for corruptions.