The community around simplecov provides a whole bunch of alternate formatters beyond the official simplecov-html gem.
If you have built or found one that is missing here, please send a Pull Request for this document!
by Matt Hale
A formatter that generates a coverage badge for use in your project's readme using ImageMagick.
by Jesse Bowes
A formatter that generates Cobertura XML.
by Fernando Guillen
CSV formatter for SimpleCov
by Vicent Llongo
JSON formatter for SimpleCov
by Fernando Guillen
"The target of this formatter is to cheat on Hudson so I can use the Ruby metrics plugin with SimpleCov."
A formatter that prints the coverage of the file under test when you run a single test file.