Only these payed subscription ones that offer a human translator. But I never tried those so I can't tell. Its probably very difficult because subtle ways of mentioning things go lost.
Example: "Barking up the wrong tree" would be an understandable proverb by english speakers, after translating it to chinese it becomes literal and people go "lolwut?". Chinese (elaborate ones) use a lot of nods to philosophers, politicians and historic (or legendary like journy to the west or three kingdoms) events. Just because we have tons of it after 4000+ years of history (just see how much quotes you get alone from 200 years of US history with general Grant, Lincoln and whatnot, see how awefully much references we have available XD? Just Sun Tzu, Mencius or Konfucius alone suffices to cover everything ever said by anyone.)
But the most elaborate Chinese gets reduced to a "internet noob" if he's forced to use english and only knows broken engrishy ways of talking... XDDD
But for the average guy on the web online translators do go well, provided he doesn't 1337 and uses correct grammar.