No. ROT13 and Caesar ciphers offer no real protection and are trivial to reverse. They are meant for puzzles and obscuring spoilers, not security.
Yes. ROT13 / Caesar is completely free with no sign-up, no watermarks and no usage limits.
No. ROT13 / Caesar runs entirely in your browser, so your data never leaves your device.
Only your device's available memory — there are no server-side limits because nothing is uploaded.
Apply a ROT13 or custom Caesar cipher shift to your text.