ProWritingAid

ProWritingAid is a grammar and style checker that goes further than spotting mistakes. Alongside spelling and grammar, it runs reports on things like overused words, sentence length variety, sticky sentences, pacing and dialogue tags, which is why many fiction and nonfiction authors use it on full manuscripts.

It works in a web editor, through a browser extension, and inside Microsoft Word and Google Docs. It also connects to Scrivener, a writing app many novelists use. A free version checks a limited amount of text, and paid plans remove the limits.

The reports are a lot to take in at once. Most writers pick two or three reports that match their known habits and run those on each chapter, rather than chasing every flag.