HashCalc Publisher: SlavaSoft Platform: Windows 9x/ME/NT/2000/XP License: Freeware Downloads: 62

HashCalc is a fast and easy-to-use calculator that allows to compute checksum values and HMACs for files, as well as for text and hex strings. It offers a choice of 13 of the most popular hash and checksum algorithms for calculations.

What is checksum value?

Checksum is a calculated value that is used to determine the integrity of data. The sender of the data calculates checksum value by taking the sum of the binary data transmitted. When receiving the data, the receiver can perform the same calculation on the data and compare it with the checksum value provided by the sender. If the two values match, the receiver has a high degree of confidence that the data was received correctly.

Checksum value is also called hash value. The data that is calculated can be a file, a text string, or a hexadecimal string.

The most commonly used checksum is MD5 (Message-Digest algorithm 5) hash. MD5 was designed by Professor Ronald L. Rivest in 1991 to replace an earlier hash function, MD4. MD5 checksum is a 128-bit hash value (32 characters).

Use of checksum values

In practice, checksum value is mainly used in two situations.

1. First, it can be used to check data integrity when data is sent through telecommunication networks such as Internet.

2. Second, it can be used to check data integrity of stored data to see if the data has been modified or changed in any way over time.

HashCalc is such a free utility that you can easily install to calculate checksum values of any files.

Here is a list of main features of HashCalc:

• Support of 13 well-known and documented hash and checksum algorithms: MD5, MD4, MD2, SHA-1, SHA-2 (256, 384, 512), RIPEMD-160, PANAMA, TIGER, ADLER32, CRC32.

• Support of a custom hash algorithm (MD4-based) used in Peer-to-Peer eDonkey and eMule applications. Peer-to-Peer (P2P) application runs on a personal computer and shares files with other users across the Internet. This way, individual computers can share files each other instead of having to go to a central server for file uploading and downloading. HashCalc can be used to calculate the checksum values for files you receive from eDonkey and eMule Peer-to-Peer systems.

• Support of 2 modes of calculations: HASH/CHECKSUM and HMAC.

• Support of 3 input data formats: files, text strings, and hex strings.

• Work with large size files. (Tested on file sizes up to 15 GB).

• Support Drag-and-Drop operation. Just dray your file from Windows Explorer and drop it into HashCalc's Data field.

• Quick and simple installation and uninstallation.

• Calculates hash/checksum and HMAC for files of any type: music, audio, sound, video, image, icon, text, compression, etc., with the extensions: .mp3, .wav, .avi, .mpg, .midi, .mov, .dvd, .ram, .zip, .rar, .ico, .gif, .pif, .pic, .tif, .tiff, .txt, .doc, .pdf, .wps, .dat, .dll, .hex, .bin, .iso, .cpp, .dss, .par, .pps, .cue, .ram, .md5, .sfv, etc.

SlavaSoft also offers a free command line utility FSUM for file integrity verification.