WordCounter.net - Count words, sentences, paragraphs etc.
Popclip - PopClip appears when you select text with your mouse on your Mac.
TextPipe - Search and Replace, Find and Replace, Web Sites, Database Extracts, XML, CSV, Tab, mainframe COBOL data and more
Pantherbar - Pantherbar is a tool that lets you perform instant actions when selecting text.
NimbleText - NimbleText is a text manipulation and code generation tool available online or as a free download.
Universal Tip - Programmable tooltip that can be used with every macOS app