The U.S.-led coalition has dropped nearly 500 warheads in and around Kobani over the past three weeks, according to Defense officials.  

Pentagon press secretary Rear Adm. John Kirby said at a media briefing  Wednesday, “We know we’ve killed somewhere on the order of several hundred of their fighters from these airstrikes.”
A defense official who did not want to be identified said Wednesday that the number killed was in excess of 350. 

That is not a negligible number. But it is put into perspective by recent reports that as many as 9,000 ISIS fighters have streamed to the town to take on 3,000 Kurdish fighters who are seeking to repel the ISIS advance.