Which hash methods do you use?

Okay, so after a long time I am considering an update. Maybe I will finally take this out of beta.

One thing that I think is necessary is a native 64-bit version, so I can provide an Explorer shell plugin. This is no trivial matter — the code for many of the hash algorithms doesn’t compile in 64-bit architecture, so they need to be updated.

I don’t want to spend a lot of time doing that.  So, reply here and let me know which hash methods you actually use. As far as I am concerned, MD5 and SHA are the only ones that actually matter.

54 thoughts on “Which hash methods do you use?

  1. David

    I’d love to see 64 bit, as it would also be faster, and as of about 2012, most machines are now 64 bit OS. I know I won’t install anything else.

    All I ever use is the SHA-256 (SHA-2?), but would LOVE to see the new SHA-3, too.

    BTW, I would love to see some kind of feature to check all checksum files in a directory (one at a time). I don’t need it often, but when I move a lot of data, I’d love to be able to just point it at a directory, and let it run for a day or week. (directory=foo, extension=.bar ???)

    Oh, can I ask for an android version too????? 😉

  2. rogerms

    I’ve been using ExactFile for some time “as is” and it has worked just fine. I use it to create/check MD5 and SHA checksums. I think that just fixing any known bugs and adding a native 64-bit version would be enough of an update. (And please don’t creak what already works! 🙂

    Thanks for creating a very useful program!

  3. macex

    Yes, I agree about MD5 and SHA, but once in a while I come across SFV, and when I do, I’m grateful for ExactFile. Looking forward to 64-bit!

  4. Joe

    I recently found your program mainly because I wanted to generate .md5 files of ISOs that were created earlier. The one feature I wish your program had was the ability to pick out an individual file and use that to make the md5 file instead of generating one md5 file for the whole directory. I currently place just 1 iso at a time in an empty directory to get what I need.

    keep up the good work!

  5. goesto11

    I request CRC as well. It’s older (I think) and probably not as good, but it’s still used a lot.

    Thanks for making a great program and I look forward to the updated version.

  6. Just me

    SHA256, and Whirlpool.

    In simple terms, once one moves beyond SHA1 and the venerable MD5, sHA256 and Whirlpool are the common choices and with more powerful machines, my impression is they are fairly widely used. (Full disk encryption packages for example, often use those two). Certainly I use both.

    Probably want to think about the new SHA-3 that was announced a few months ago, as well?

  7. Dominik Schuierer


    i like the software very much – use the command line version.

    But there is something “special” I´m missing:

    Why is it not possible (or did i miss that) to create an “.md5” file for every file in one directory (named according to the source file)?

    best regards


  8. Kevin04

    Personally, I pretty much exclusively use CRC32, MD5 and the SHAs. Very rarely do I need any of the others provided by ExactFile.

    However, an additional method I’d like to see in the program is the eD2k hash. It’s used by some projects I’m contributing to, and it’s the only hashing I don’t (can’t) use ExactFile for.

  9. Jack


    I have been waiting a LOOOOOOONG time for you to get going with updating this software.. I keep checking back every few months.. its been years!
    MD5 and SHA are fine for 64bit. Just make this software a bit better, I don’t care if you charge a few dollars for it – just do it!
    I use it to hash a photo archive of 6 Terabytes (0.7 million files) to make sure none of the files are getting corrupted from drive degradation. Please keep in mind some of us really do use your software for serious stuff and dealing with big directories is a must!
    Thank you.

  10. Caesar

    Hi Brandon,
    I’d be very happy with 64 bit only supporting MD5 and SHA but what I would really want is wht some of the others have asked: include a “hash new files / delete hashes for files that don’t exist / ignore existing hashes” mode (to quickly update a checksum file. I’d also want to ignore folders completely, store the hashes based on filenames only (in my case, i can guarantee uniqueness). The use case is I have a 150,000 image photo library that keeps growing but i also continuously reorganize the folder structure (as well as delete some files). I use Microsoft SyncToy to keep my backups in sync with the master but I also want to be able to independently validate the master / any backup. So I want a validate checksums for existing fils (ignore location) + delete missing checksums + create checksum for new files mode.
    Thanks in advance!

  11. Thomas Eifert

    Although I’ve tried Exactfile in the past, I’ve been using FileVerifier++, mainly with MD5 and SHA-256, to maintain my binary file archive. It works well with both methods, and it’s fast too. Although it would be great to see a mass-verifier utility in development, what really seems to be difficult to find ATM (especially in a Windows environment) is a standalone single-file verifier that will do SHA-256. I have some that will do MD5 and SHA-1, but not SHA-256.

    I’ll be keeping an eye on this page for continued development of Exactfile. I look forward to future versions.

  12. seidweise

    Hey I use your app quite frequently, one odd thing that strikes me is why do the hashes output with lowercase letters? I don’t see any settings/options for this. Most hashes are displayed with upper case letters and I find it annoying to have to convert the case. Other than that every thing is perfect.

    I use sha256, md5 and crc32.
    In many communities I am part of, files are distributed as the following manner: NAME_NAME_[CRC32HERE].ext kit might be useful to have an extension that identifies this pattern and you can right click to verify? (or verify multiple files at once?)


  13. Dan Bailey


    I just came across this software (6/25/2013 )for the same purpose of ensuring my photos and other un-replaceable does not fall victim to silent corruption/bit rot.
    This is by far the best GUI and fastest of what I’ve seen so far.
    I’m trying a few others as well, one feature that I’d like to see is the ability to control what data is captured in the file output, the file name, directory with tabs or semi column for easier management with excel, plus adding last file modified data, and file size. maybe add a view to compare new/modified/missing files in the GUI as well. Similar to the way the information is presented in md5calculater.
    One last suggestion would be to add a scheduler to run say monthly with some sort of alarm when existing checksum data has changed for a file name or add some parameters around what will trigger the alarm. This may provide time to restore a file from backup in case of corruption.
    Great Tool, none the less. Thanks.

  14. Alex

    I use md5 only. I have a problem though: sometimes some letters in the file names in cyrillics are not recognized when checking for md5 (very randomly) and the files are marked as missing.

  15. Jason

    Would be so good to see a native 64bit compile of this & explorer shell integration.

    Agree with what most have said, please keep:
    -CRC32 (for legacy)

    New additions (SHA-3 & Whirlpool?) would be appreciated, but not required.

  16. aldiney

    Dear Brandon
    Have you think about open the source code ? Then more people can work on it, as you said don’t have time to work on this free application. We can work on most used hash method and lets others as plugins. What do you think about ?

  17. mike

    I would like to see an automatic 2nd attempt to check a file if the first one does not match. Right now I get checksum failures very occasionally on my photos (like 1 in 50,000) that check just fine when I do a second check manually. Otherwise its an awesome tool IMO. Txs Mike

  18. Jeff

    Hi Brandon,

    I only use CRC32, MD5, and SHA1.

    My request is just to make the explorer shell integration and recursive directory file checking and creation (i.e. be able to right click a file or entire folder to create/check MD5 files) work flawlessly. It’s such a time saver. This way programs like hkSFV can finally rest in peace and be superseded. ExactFile is already a really good program but with the same level of explorer shell integration as hkSFV for example it would be irreplaceable as no other software that I am aware of can do this.

  19. Alan

    Hi Brandon.
    I understand that the newest intel cpus have some built-in functions to speed up hashing calculations (although I may be wrong about how useful they are). Do you think that your new 64-bit version will make use of them to speed things up even more on the relevant computers ?

    I’d also like to know how many cpu cores your program can utilise at one time.

    – Alan

  20. John

    Still one of the most useful tools in my software collection!
    Patiently waiting for that magical update..

  21. ffrree

    I was wondering if there is a way to also include hidden files & folders when creating Applet for a folder & its sub folders.

    Also is it possible to exclude all sub folders?

    Appreciate your great work.


  22. Danny

    I think the program is great, just started using it! Only 1 request I would like to see automatic scheduling of checks with an email sent if anything is found to be corrupted so a restore from backup is possible.

  23. Lorenzo

    I also have experienced an issue similar to the one reported by Alex (post July 18, 2013 at 10:10 am), namely sometimes some files with non-ascii filenames (Polish letters in my case) are not found at the `Test digest’ phase, although the files are there and, if checked using `Single File checksum’ they check out fine. I’m using MD5 hashes only. My wish-list:
    1) The progress bar now counts the number of files processed; it’d be better to count the bytes processed out of the total to do.
    2) It’d be nice to see an `estimated time to completion’ and perhaps the speed in MB/sec.

  24. Peter

    First of all thank you for all the hard work that you have put in this project!
    I use mainly MD5 (for video/pictures). Native 64bit with shell extension would be incredible!
    My list: CRC32/SFV (for legacy), MD5 and the SHAs.

  25. Dan

    Thanks very much for ExactFile! I’ve used it for many years, and I made a small donation years ago.

    Since I’m only interested in file integrity checksums, I use your crc32 and md5 options exclusively. I use CRC-32 for photos (each less than 50MB) and MD5 for MP4 videos (all less than 1GB).

    I realize my use-case is specialized. So, I’ve written software (currently being rewritten again) for my own use. But I continue to use ExactFile for trusted checking of my generated checksums. The computational cost of a checksum for my photos is important to me because I overlap it with I/O and have chosen Python (single threaded), to implement it.

    My impression is that CRC-32C is superior to CRC-32 (ISO) and is becoming the new standard for a 4 byte checksums. For this reason, I’d like you to support CRC-32C in your next version.

    Here’s a link to open source C, for an implantation:


    Thanks again,


  26. Dan Zemke

    Thanks very much for ExactFile! I’ve used it for many years.

    I’m only interested in file integrity checksums (as opposed to secure hashes to detect authenticity/hacking). I use CRC32 to verify the integrity of my photos. But I would prefer to use CRC32C (Castagnoli) instead. It’s better at detecting unintentional errors at a very low computational cost, like CRC32. An indication of the desirability of CRC32C is that Intel added a hardware instruction, specifically for it, in SSE 4.2 (first customer ship 2008, now mainstream for new desktop CPUs).

    Please add CRC32C as one of your supported hash methods in a future release of ExactFile.


  27. Brandon Post author

    Every time I think I can sit down and work on ExactFile, something else comes up. 🙂 I don’t see any changes in the foreseeable future right now.

  28. Sean M. Brannon

    I just came across ExactFile and see that you are considering adding a 64-bit version and are concerned about making your hashing code 64-bit clean. My first thought was to suggest you leverage md5deep/hashdeep’s code. It supports both 32-bit and 64-bit, and “…is a set of programs to compute MD5, SHA-1, SHA-256, Tiger, or Whirlpool message digests on an arbitrary number of files.” Most of the code is in the public domain as a U.S. gov’t product, tho the Tiger hashing uses libgcrypt and is licensed under the GPL. See http://md5deep.sourceforge.net/ and https://github.com/jessek/hashdeep/

    Hashdeep is all CLI and might be perfectly suitable for your needs. Perhaps both projects could collaborate.

    Thank you for all your work on ExactFile!

  29. sepp spenlinhauer

    Just getting into this and your my first stop on this journey… But in my first usage, to check multiple Image Archives going back to the first digital camera, circa 1999, is to provide a way to exclude file types.
    In this case, the thumbs.db is useless to check because it is re-constructed constantly.
    I’m sure there are other formats that users might want to exclude too.


  30. Debby

    I love this program. It would be awesome to see a 64-bit update to this program and one that doesn’t say Beta. The hashes that I’d like to see are: SHA-1, SHA-2, SHA-3, and the TIGER192 and the other TIGER hashes. One problem with this program is that if any file/folder that is checksumed is unreadable (such as on a DVD) the program will stop, ignore the errors and show zero errors (the progress bar won’t be filled however) which is deceptive and has fooled me a few times. Too, I wish it did show a dialog box at the end saying (as well as the progress bar) that no errors were found.

    Thanks. 🙂

  31. booradlly

    Any chance you could make this OpenSource??
    So at least other people could fork it? If you don’t want people working on the core source?
    This should also increase people donating, as the donations would still go to you, even if other people were working on it.
    The program is awesome, but its soo slow in comparison to whats possible, and there are very few other options that do what this program does (batch hash checks for file integrity).

  32. Brandon Post author

    I have addressed this in other posts. ExactFile uses closed-source third-party components and is written in Delphi. I am not interested in doing the work to remove the proprietary parts in order to open source it.

  33. Mark

    Hi Brandon,

    i would love to see a 64 bit version. I´m on 2 64 bit machines using Windows 7 (Desktop) and Windows 10 (Notebook). My most used hash algorithms are sha-1, sha-2 and crc32.

  34. Matthew

    I just wanted to post that I really appreciate this software. It’s just crazy that there’s not more programs like this out there for Windows. It’s so easy to use and relatively fast that I don’t know what I’d do without it.

    I use Fastcopy which has a verification feature to confirm all copies are good but this software helps to insure that my archived data doesn’t get corrupted due to a bad disk, bad memory or whatever other gremlins pop up in everyday computer use. I’ve even reformatted some of Fastcopy’s log files to use as verifcation digests in Exactfile.

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