I recommend against using the linked tool. If text is pasted into a textarea widget, even one change in line breaks, etc. would change the output hash and make it irreproduceable. The only other option on that form appears to be a URL for a file hosted somewhere online. It appears that this form (?) sends the data to the server to be hashed (not sure).
You are right.However,they also have an option to upload the file manually which I believe can prevent the space errors but comes with a vulnerability of file being manipulated/stored on their servers.I can't think of anything else which does the compression effectively without opening a CLI.
(Nit: SHA-256 is not an encryption algorithm. It is a cryptographic hash. The objective is not to encrypt the script, but to put it through a one-way compression. There is no way to decrypt SHA-256. The process is only one-way.)
Thanks,I do need to revise my basics.