Heytools - JavaScript tools, AJAX tools and some fully server side tools.
Reading Time - Tells you how long an article takes to read
WordCounter.net - Count words, sentences, paragraphs etc.
Read Time - Webpage read time estimator chrome extension
NimbleText - NimbleText is a text manipulation and code generation tool available online or as a free download.
Minimal Reading Mode - Optimize websites for reading: font, contrast, night mode