What Is an SFV File?

SFVs verify information using checksum values

A Simple File Verification file is used to verify data. A CRC32 checksum value is stored in a file that usually, though not always, has the .SFV file extension appended to it.

How Are SFV Files Used?

A program that can calculate the checksum of a file, folder, or disk, is used to produce the SFV file. The purpose is to verify that a particular piece of data is truly the data you expect it to be.

The checksum changes with each and every character that's added or removed from a file, and the same applies to files and file names within folders or disks. This means that the checksum is unique for every single piece of data, even if one character is off, the size is slightly different, etc.

For example, when verifying the files on a disc after they've been burned from a computer, the program doing the verifying can check that all the files that were supposed to be copied actually do exist on the CD.

The same is true if calculating the checksum against a file you've downloaded from the internet. If the checksum is calculated and shown on the website, and you check it again after it's downloaded, a match can assure you that the same file you requested is the one you now have and that it wasn't corrupted or purposefully modified in the download process.

SFV files in Windows 10 that are opened with Notepad

SFV files might sometimes be referred to as Simple File Validator files.

How to Run a Simple File Verification (Make an SFV File)

MooSFV, SFV Checker, and RapidCRC are three free tools that can generate the checksum of a file or group of files, and then place it into an SFV file. With RapidCRC, you can create the file (and even an MD5 file) for every single file in your list or every directory, or even make just one SFV file for all the files.

Another is TeraCopy, a program used to copy data. It can verify that they were all copied and none of the data was dropped along the way. It supports not only the CRC32 hash function but also MD5, SHA-1, SHA-256, Whirlpool, Panama, RipeMD, and others.

Create an SFV file on macOS with SuperSFV or checkSum+. You can use Check SFV if you're on Linux.

QuickSFV is another that works on Windows and Linux, but it's run entirely through the command line. For example, in Windows, with Command Prompt, you have to enter the following to produce the SFV file:

quicksfv.exe -c test.sfv file.txt

In this example, -c makes the file, identifies the checksum value of file.txt, and then places it into test.sfv. These commands assume that the QuickSFV program and TXT file are in the same folder.

How to Open an SFV File

SFV files are plain text, which means they can be viewed with any text editor like Notepad in Windows, Leafpad for Linux, and Geany for macOS. Other free text editors support the format, too, like the popular Notepad++.

Some of the programs from above that calculate the checksum, can also be used to open SFV files (TeraCopy is one example). However, instead of letting you view the plain text information held within it as a text editor does, they normally will open the SFV file or file in question, and then compare a new checksum test against the one you have.

These files are always created like this: the file name is listed on one line followed by a space, which is then followed by the checksum. Additional lines can be created below others for a list of checksums, and comments can be added using semicolons.

Here's one example of an SFV file created by RapidCRC:

; Generated by WIN-SFV32 v1 (compatible; RapidCRC http://rapidcrc.sourceforge.net )
uninstall.exe C31F39B6

How to Convert SFV Files

An SFV file is just a text file, which means you can only convert one to other text-based formats. This might include TXT, RTF, or HTML/HTM, but they usually remain with their SFV file extension because the purpose is just to store the checksum.

Because of this, you can't save your SFV file to a video format like MP4 or AVI, or any other kind like ISO, ZIP, RAR, etc.

Troubleshooting SFV Files

It's unlikely that a regular text editor will automatically recognize SFV files. If this is the case, and nothing happens when you double-click to open it, try opening the program first and then use the Open menu to browse for the file.

If you do want your text editor to recognize and automatically open SFV files in Windows, you can change file associations.

Some file extensions might look an awful lot like SFV files but are in fact not related to them at all. This is the case with ones like SFZ, SFM, and SVF (a vector file format).

SFVIDCAP is an interesting file extension that starts off with the same few letters, but it's really just a coincidence. It's used by a format that stores videos for a video editing program.

Also, remember that SFV files are sometimes stored along with videos. In this collection is often an SRT file used for subtitles. While the two formats are text-based and might look similar in name, they aren't related and can't be converted to or from the other format for any useful purpose.

  • Can you safely delete .SFV files?

    Yes, you can. .SFV files are most often used for verification purposes and/or provide information: They aren't required for a program or app to function.

  • What are .SFV files used for?

    Primarily, they are used to verify files are not corrupted. An .SFV file cannot guarantee a file is safe or does not contain malware, however.

Was this page helpful?