A checksum is also sometimes called ahash sumand less often ahash value,hash code, or simply ahash.
Checksums really aren’t that hard to understand or create.
Let’s start with a simple example, hopefully showcasing the power of checksums to prove something has changed.
The MD5 checksum for the following phrase is a long string of characters that represent that sentence.
For our purposes here, they essentially equal each other.
However, making even a slight change, like removing justthe period, will produce a completely different checksum.
This is probably a huge file, taking several minutes or more to download.
Once downloaded, how do you know the file was received properly?
This is where comparing checksums can put your mind at ease.
Do the checksums match?
you’re free to be very confident that the two files are identical.
Do the checksums not match?
Just compare the hash you create with the one available from the file’s source.
Checksum Calculators
Checksum calculators are the tools used to compute checksums.
There are plenty of them out there, each supporting a different set of cryptographic hash functions.
It supports only the MD5 andSHA-1cryptographic hash functions, but these are by far the most popular right now.
Microsoft File Checksum Integrity Verifier is acommand-lineprogram, but is very easy to use.
If you’re not comfortable with command-line tools, this tool is probably a better choice.
It supports MD5 and SHA-1, as well as CRC32.
you’ve got the option to use it to find the checksum of text and files.
A Built-in Windows Calculator
you could also use thecertutilprogram built-in to Windows.
That article also describes how to do the same on Linux withmd5sum.
FAQ
Yes.
Only files that are identical will have the same checksum.
Changing anything other than the file name will result in a different checksum.
you’re able to get the checksum of multiple files at once using the MD5command.
pop swing open the terminal and typemd5followed by each file name (separated by spaces), then pressEnter.
