Board Thread:General Discussion/@comment-7489479-20130330224439/@comment-4674838-20130331031658

Most of the monster pages here on the wiki list the item drop chances when you kill that monster a single time &mdash; you will find this information in the infobox in the upper-right corner of the page.

For example, the Big Stinger monster has a 50% chance to drop a Stinger item, as you can see in the Drops section of the infobox.

These drop chances were pulled directly from the source code of the PC version of Terraria, I believe. (As in, someone decompiled Terraria, read the source code of the game, noted the drop chance in the game code, and then wrote that number here on the wiki.) &mdash; see w:c:tconfig:How to Decompile Terraria for more information about obtaining the game source code.