There are several online spelling and grammar programs available from providers like Ginger, Whitesmoke and Spellchecker, which is associated with the program Grammarly. These applications are free and text can be copy pasted into most online spell checkers, but some require apps downloaded to a user's browser or to their computer. The extensions or apps for computer browsers are usually free, but more information can be found on the program's website.
Most of the free checkers have larger more detailed programs that are available for purchase or download if someone is using only the online versions. The options offered from various program providers vary, so not all of the programs may serve the user's needs.