shell - Generating a SHA-256 hash from the Linux command line

Question

I know the string "foobar" generates the SHA-256 hash c3ab8ff13720e8ad9047dd39466b3c8974e592c2fa383d4a3960714caef0c4f2 using http://hash.online-convert.com/sha256-generator

However the command line shell:

hendry@x201 ~$ echo foobar | sha256sum
aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f  -

Generates a different hash. What am I missing?

Answer 1

echo will normally output a newline, which is suppressed with -n. Try this:

echo -n foobar | sha256sum