How can I count the frequency of every word in a PDF using Python?

First convert the PDF into plain text, using a tool such as pdftotext or a Python PDF library. Once you have the text, Python’s collections.Counter can count the words. You can tokenize the text into words, normalize them to lowercase, and pass the resulting list to Counter. The keys will be the unique words and the values will be their frequencies.

You could also load the extracted words into a database and use a grouped count query, but that is probably more setup than you need for this project. Python’s Counter is designed for exactly this kind of frequency analysis.

If you already have the book as plain text, this is straightforward in Python: use a regular expression or another tokenizer to extract words, convert them to lowercase, and run Counter on the list. That will give you a dictionary-like object containing each word and its count. The main challenge is extracting clean text from the PDF, especially if it contains scanned pages or unusual formatting.