Jetpack already provides you a module for After the Deadline proofreading service for improving your writing via artificial intelligence to find your errors and offer smart suggestions. It also provides a number of customization options which you can easily set from your profile (Dashboard -> Users -> Your Profile).
The service checks for:
- Contextual Spell Checking
- Advanced Style Checking
- Intelligent Grammar Checking
But if you are not a Jetpack user then you can use TinyMCE Spellcheck. The plugin is a fork of the After the Deadline plugin which is now a part of popular Jetpack plugin.
How To Spellcheck Your Content?
After you finish writing your post, just click the spellcheck button and it will show you the mistakes and suggestions. Clicking the errored words drops down the corrections suggested by the plugin.