[tr4nslator]

Or for a more quantitative approach, with 1.7 Chinese characters per English word[1] and an average English word length at 5.1 letters[2], then somewhere around 420 characters.

(But of course, it really depends on the nature of the text.)

[1] http://itre.cis.upenn.edu/~myl/languagelog/archives/002379.h... [2] http://blogamundo.net/lab/wordlengths/