Wordeep Proofreading
Does exactly what it promises to do. It catches errors and offers alternatives. Most importantly, it offers the option to ignore its suggestion. This is particularly important when dealing with UK and USA variants.
It's rejected the password I want to use, saying it needs to be more complex, but doesn't say what your password rules are. My password formula is accepted by 99.99999% or more of sites I register at. It has upper and lower, numbers, and non-alphanumeric characters. Why not tell us the requirements instead of making us play a guessing game? It's bad marketing to reject customers before they even get to try your service. Can't even try it in the text box on your website.
HIGHLY RECOMMEND! Excellent tool and it finds more grammar mistakes than other grammar checks that I have tried.
http://www.prowritingaid.com/
Essential Kit
Grammar Checker
https://sapling.ai/
https://upwriteai.com
https://contentyze.com/
https://outwrite.com
nchathu2014
https://linangdata.com/
https://scribens.com
joncazier
https://wproofreader.com