Diagram of Will Future and Going to Future

A diagram to show usage of the will-future and going to-future

Both tenses are future tenses.

We use the will-future for predictions, assumptions, promises and when we do something spontaneously. Here you can see the decision is made “now” and the action is still in the future:

• Are you cold? I will (1) close (2) the window.

We use the going to-future with planned actions. The decision about the action is in the past but the action is still in the future:

• Where are you going? I am going to (1) close (2) the window.