File Checksum Tool
==================

Free and portable. It runs without installation, from any folder or a USB
drive. Settings are kept in the registry under
HKEY_CURRENT_USER\Software\Krylack\File Checksum Tool.

https://www.krylack.com/file-checksum-tool


There's also a setup (hashtoolsetup.exe on the website) that adds a Start menu
entry, "Calculate checksums" in the Explorer menu and an uninstaller. It installs
all the files below, so its program folder is a portable copy too.


Which file to run
-----------------

  hashtool.exe         The program. Runs on every Windows from 7 to 11.
  hashtool64.exe       The same, built for 64-bit Windows. Faster with
                       SHA-512, BLAKE3 and xxHash.
  hashtoolarm64.exe    The same, for Windows on ARM.

  fchash.exe           The command-line tool (fchash64.exe and
  fchash64.exe         fchasharm64.exe are the 64-bit and ARM builds).
  fchasharm64.exe      Run "fchash --help" for its options.


Checking a download
-------------------

1. Drop the downloaded file onto the window (or use Add Files).
2. Copy the checksum from the download page and click Paste next to
   "Expected hash". The algorithm is detected from the hash itself.
3. A green "Match" means the file is exactly the one the website published.

The details below the list also show who signed the file and the address it
was downloaded from, when Windows recorded it.


Command line examples
---------------------

  fchash setup.exe                      SHA-256 of a file
  fchash -a md5,sha1,sha256 *.iso       several algorithms
  fchash -r . > SHA256SUMS              a checksum file for a folder
  fchash -c SHA256SUMS                  verify the files it lists
  fchash --expect <hash> setup.exe      compare with a published hash

Exit codes: 0 all OK, 1 a hash didn't match, 2 wrong usage, 3 a file couldn't
be read. Checksum files use '/' in paths and LF line ends, so Linux
"sha256sum -c" reads them too.


Algorithms
----------

MD5, SHA-1, SHA-256, SHA-384, SHA-512, SHA3-256, SHA3-384, SHA3-512, BLAKE3,
CRC32, XXH64, XXH3-64, XXH128, and the legacy MD2 and MD4 (Options menu).
MD5, SHA-1, CRC32 and xxHash detect accidental corruption but aren't safe
against deliberate tampering. Prefer SHA-256 or newer when a site offers it.


Windows 7
---------

The programs are signed with a SHA-256 certificate. Windows 7 needs the SHA-2
code signing update (KB4474419) to check such signatures. Nearly every updated
Windows 7 computer has it.


Copyright (C) 2026 Serhii Horobets. Freeware, see LICENSE.txt.
support@krylack.com
