Newly revised this morning: http://www.python.org/dev/peps/pep-0008/#maximum-line-length summary: 72 for text block (comments, triple-quoted strings) 79 for normal code 99 for code that is really more readable with extra The diff with all the changes is here http://hg.python.org/peps/rev/fb24c80e9afb -- Terry Jan Reedy