This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
To any future monthly posters of SQ threads, please remember to add the "stupid_questions" tag.
Unless your text is very short or your key very long, they are much easier than you apparently think. I have written programs that do a pretty good job of it.
(As MrMind says, if your key is as long as your text then this is a one-time pad, which indeed is uncrackable provided you have a reliable channel for sharing the one-time pad and don't make operational mistakes like reusing the key. But that's not a very common situation.)
I agree that I made my key too long so it's a one-time pad. You're right.
"Much easier"? With or without word lengths?OK, no obligation, but I didn't make this too brutal:
Vsjfodjpfexjpipnyulfsmyvxzhvlsclqkubyuwefbvflrcxvwbnyprtrrefpxrbdymskgnryynwxzrmsgowypjivrectssbmst ipqwrcauwojmmqfeohpjgwauccrdwqfeadykgsnzwylvbdk.
(Again, no obligation to play, and no inference should be taken against gjm's hypothesis if they decline.)