When comparing Coursera vs exercism.org, the Slant community recommends exercism.org for most people. In the question“What are the best websites to learn to code?” exercism.org is ranked 2nd while Coursera is ranked 9th. The most important reason people chose exercism.org is:
Rather than merely test for code correctness, Exercism uses peer review to improve general programming techniques. Users are encouraged to comment on others' solutions, and refine their own based on feedback.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Some courses offer a verified certificate for a fee
There is an option to earn a verified certificate as proof you completed the course (for use on LinkedIn, resumes etc.). The cost varies between courses, but is generally around $49-$60.
Pro High quality courses from well known universities
Many courses offered at Coursera are from well known universities (such as Stanford and Princeton) and instructed by their professors. Often the material taught in the Coursera courses is material from the actual university course.
Pro Wide selection of courses
Coursera offers over 1000 courses on a variety of different topics. Courses are offered on learning to code and specific languages, but there is also a large selection of courses that would be beneficial to someone wanting to learn more about computer science as well (algorithms, data science, computer security) and plenty others.
Pro You can audit courses for free
Pro Courses offered in a variety of languages (with transcriptions available)
Coursera offers courses from all around the world, resulting in courses taught in English, French, Spanish, Chinese, Russian, Turkish and a long list of others. Transcriptions for a large number of languages are offered for each course.

Pro Human review and feedback
Rather than merely test for code correctness, Exercism uses peer review to improve general programming techniques. Users are encouraged to comment on others' solutions, and refine their own based on feedback.

Pro Practice with production tools
Unlike many code practice websites, Exercism requires the user to develop and test entirely offline, submitting only the finished code. This promotes familiarity with essential tools and workflow, not just the bare language.
Cons
Con Courses are not always available
Courses are run on set dates, though some courses provide access to the material whether or not the course is running (however, there will be far less student activity in the forums when the course is not running).
Some courses only make their material available when the course is running, so you may have to wait a long period (sometimes months) for your course to be offered.
Con You cannot take the full courses for free
While you used to be able to take courses for free and earn a statement of accomplishment, this is no longer the case. You can only audit the courses if you are not paying. Coursera makes it seem like you should also do the quizzes, but the submit button says "Upgrade to submit".

Con Custom commandline client
Exercism requires using a CLI utility to fetch and submit exercises. This is inconvenient compared to web-only alternatives, and poses an additional barrier to entry for some users.
