File checksum calculator
Checksum calculations are used to precisely identify a file. There are many algorithms to accomplish that. This tool serves with 3 widely used algorithms, which are:
There are at least two different types of CRC32 that are commonly used. CRC32 and CRC32b. Both give different results. CRC32b is widely used and is therefore commonly referred to simply as CRC32. This often leads to confusion. This tool uses CRC32b, which results in a 32-bit hash value which is represented by an 8-digit heximal string. CRC checksum calculation is outdated nowadays since the CRC algorithm has too many collision.
MD5 (Message-Digest Algorithm 5) results in a 128-bit hash value which is represented by a 32-digit heximal string. This algorithm is essentially more complex than CRC, but also leads to collision. On this page you will find some sample files that produces a MD5 collisions.
SHA1 (Secure Hash Algorithm 1) results in a 160-bit hash value which is represented by a 40-digit heximal string. A collision was also found in this algorithm, which is described here: https://shattered.io/. If you download PDF 1 and PDF 2 and calculate the checksum, you will get an identical SHA1 checksum, even if the two PDF files have different contents.
I created a sample file to compare the checksum results with other tools. This file can be downloaded here. The checksum calculator generates the following checksums for this file:
To compare the results with other tools, I recommend this page with many different checksum algorithms.
There are many different ways to calculate the checksums with this tool. For example:
- Button «Select a file»
- Drag&Drop a file on the window
- Command line parameter
- Version 1.0: Initial version
- Version 2.0: Corrects a bug with file symbols
Categories: Windows Tools