CrcCheckCopy - Features

CrcCheckCopy is our file and folder comparison utility that works by verifying the files by their CRC32 hash checksum.

Main features

• Runs recursively: compares the files of one folder and all its subfolders.
• Finds and reports duplicate files (searches for identical files), even when they have different filenames.
• Heavy-duty, industry-tested: reliably compares hundreds of thousands of files. Has been working for the CD Rom, DVD Rom and backup industry and professionals for more than two decades.
• Does not "choke" on filenames with peculiar characters.
• Based on the idea of comparing the CRC hashes of two files instead of a byte by byte comparison: When scanning the source (reference) folder, the program saves the CRC hash and the file size of every file inside a single text file, named "CRCstamps.txt".
• Process the file list by importing it to an Excel spreadsheet. The file list with the file sizes and the file CRCs is a space-separated file and as such you can directly load it into excel or OpenOffice calc. There, you can filter and sort the list, and create .bat script files to process the files.
  For example, after you merge two big disk volumes of files, you can scan them with CrcCheckCopy to have the CRCs in the CRCstamps.txt file. You can load this file in excel and create a script file to delete all the duplicate files.
• Cross-platform: it works natively under Windows and MacOS. On Linux, it works fine under Wine.
  You can scan files that reside on a Windows computer and compare them with a file set on a MacOS computer.
• Compare multiple destination disks in half the time.
  If you are creating multiple copies, CrcCheckCopy can verify them in half the time. The scanning of the source disk is done only once, while the verification can be done as many times you want, using the same checksum file. No need to read again the source files.
• The verification will skip the CRC checksum calculation if the sizes are different. This will speed up the verification process and reduce disk activity.
• No network traffic if the files reside on different servers. Can work also without network connectivity.
• Compare folder hierarchies or whole disks in remote locations (not on the same local network).
  You only need to send the checksum file from the computer holding the source files, to the computer where the destination files or disks are.
  E.g. a software manufacturer can send the checksum file to the DVD factory to verify that the final DVDs are verbatim copies of the original while having the option to accept differences in some "last minute" files.
• Store the checksum file as produced by CrcCheckCopy on every important data copy or backup you do. This will allow you (or others) to check the integrity of the files at any time in the future.
• Alternative to md5 compare function of rsync.
• Portable executable: no installation is needed.
  No administrator account needed (because there is no installation).
• Small size (Less than 0.5 Mb).
  Can be transferred easily and quickly via remote desktop connections.
• Free: there is nothing to pay and no need to register before you start using our utility. But your donation will be much appreciated.
• Not tested on animals.

Features under consideration

• A configurable (user-defined) filename for the "CRCstamps.txt" file.
• Incremental update of the file containing the CRC hashes:
  Only calculate the CRC of the new or modified files (modification based on file date and file size) OR scan only the files provided in a list.
  Then, update the previous "CRCstamps.txt" file with the CRCs of the new, updated and missing files.
• Ignore files or folders: a "-i" parameter (from ignore) that will give some file or folder names to ignore during the scanning or the verification phase. Multiple file or folder names can be separated by ';'
  E.g. -i desktop.ini;thumbs.db;tmp
  ignores files or folders named: "desktop.ini" or "thumbs.db" or "tmp".
• Show an error message if wildcards are used in the parameter for the path

Feature comparison of Free vs PRO edition