How the correction works

This tool works from a word list, not from grammar. Every word in your text is stripped of accents, lowercased and looked up in the list for the language you picked. On a match the accented spelling is put back and the capitalisation of the original is copied onto it, so manana becomes mañana, Manana becomes Mañana and MANANA becomes MAÑANA. Anything that is not in the list comes back untouched.

Words that differ only by an accent are missing on purpose. In Spanish si and sí, el and él, tu and tú, mas and más are all real words, and no tool can pick between them without reading the sentence. The same is true of French a and à, ou and où, la and là, and of Portuguese esta and está. Those pairs were left out of the lists, which is why a few accents are still missing after a run.

Treat the output as a first pass and read it afterwards. Each list holds roughly 450 to 600 of the most common accented words in that language, which covers everyday writing but not names, technical terms or rarer inflected forms. If you only need a single letter, the character pages give you the shortcut for it on Windows, Mac, iPhone, Android and Linux.