ROT47
ROT47, classical cipher, a puzzle not a protection, computed on your device.
Runs on your device. The file is never uploaded.
ROT47 shifts each character in the band from ! to ~ by 47 places inside that 94 character run, and prints the result as text. Spaces, tabs, newlines and anything above ASCII pass through, so your line breaks and your exact length survive. There is no key, which leaves recognising the output as the only step to undoing it.
Questions
What does ROT47 rotate?
Every printable ASCII character from ! to ~, which is 94 characters, shifted 47 places. ROT13 only moves letters, so it leaves digits and punctuation alone. ROT47 scrambles those too, which is why its output looks like line noise rather than like words.
How do I decode ROT47?
Run the same tool again. Applying a 47-place shift twice over a 94-character alphabet returns you to the start, so ROT47 is its own inverse. There is no separate decode tool and no key to keep.
Is ROT47 encryption?
No. It has no key, so anyone who recognises the output can reverse it in one step. Use it to hide a spoiler or a puzzle answer from a casual glance. For real protection, use AES-GCM encrypt.
What happens to characters outside that range?
They pass through untouched. Spaces, tabs, newlines and any non-ASCII character are outside the 94-character band, so line structure survives and the result stays the same length as your input.