Google Books Ngram Viewer

The program can search for a word or a phrase, including misspellings or gibberish. The n-grams are matched with the text within the selected corpus, optionally using case-sensitive spelling (which compares the exact use of uppercase letters), and, if found in 40 or more books, are then displayed as a graph.
The Google Ngram Viewer supports searches for parts of speech and wildcards. It is routinely used in research.