English Grammar Reference: Different uses of will

We use will in the following situations :

• To make an immediate decision

I'll have a ham sandwich please.

• To make an offer

I'll carry that for you.

• To make a promise

I'll pay you back tomorrow.

• To make a prediction

He will be successful.

• The first conditional

If it's hot tomorrow, I'll go to the beach.

• The future continuous

I'll be sleeping at midnight tonight.

• The future perfect simple

I'll have been to China by 2020.

• The future perfect continuous

I'll have been living here for 10 years by December.

See also:

English Grammar Reference: Differences between going to, present continuous and will