The lengths of free English courses vary depending on the structure, content and method of delivery of each course. Free English classes held at the New York Public Library are held for four hours a week for 10 weeks. Online classes last at least for a couple of hours.
Alison's short English courses can be finished within three hours, while diploma courses require around 15 hours. British Council's English courses on Future Learn take about two hours a week and last up to six weeks. In addition to English classes, language training apps such as Duolingo can improve a person's English skills and only require a few minutes per day. Spending 34 hours on Duolingo is comparable to a semester of language education.