The Roll20 API is only available to paying subscribers with a Mentor level account

The Roll20 API is still very alpha software. We strongly recommend that you only enable API scripts on copies of your campaigns, as they may be damaged.

The Roll20 API provides a powerful way to customize and enhance your game. You write scripts (little pieces of code) that tell Roll20 what to do during gameplay (for instance, move a piece, add a status marker to a token, or even roll dice). It's simple and straightforward to get started, but the possibilities are endless.

What do I need to get started?

Scripts for the Roll20 API are written in Javascript. You only need a basic understanding of the language to get started, but if you want to learn more about Javascript, this Codecademy course can help teach you.

How does it work?

You write scripts that listen to events that happen during the game. Scripts can check to make sure that rules are followed, change properties on objects and tokens, and even provide custom chat commands. The scripts you write run across the entire campaign, and affect things the GM does as well as all the players. Advanced scripts can also run independently, preforming automatic actions such as moving a token on a patrol route or nudging players when their turn is taking too long.

To get started, your first stop should be the Use Guide.