What's the difference between "estimate" and " forecast"? I never thought I would be troubled by the two words until today. 1 Economists estimate that a 5% reduction will cause the price of oil to rise. 2 Experts forecast that only a few people will be able to run cars in the future. I get confused by the two sentences. I feel the two words can be put in either of the sentences. However, the only difference I could think of is that maybe " estimate" is always followed by some exact figures. I hope someone can help me with that. Thank you.