The key question
Will
Going To
Decided NOW, at the moment of speaking (spontaneous)
Decided BEFORE — it's already a plan
Promise, offer, threat
Intention, plan, schedule
General prediction (opinion / belief)
Prediction with visible evidence (you can SEE it)
Side by side
| Situation | Will ✓ | Going To ✓ |
|---|---|---|
| Someone knocks on the door | I'll get it. (decided right now) |
— |
| You decided last week | — | I'm going to visit my parents. (plan made in advance) |
| You see dark clouds | — | It's going to rain. (evidence you can see) |
| General belief about the future | I think robots will replace many jobs. (your opinion) |
— |
| A promise | I won't tell anyone. I promise. | — |
| An offer | I'll carry that for you. | — |
Both can sometimes work:
"I think it will rain" and "It's going to rain" can both be correct, but with different shades of meaning. Will = my general feeling; Going to = I can see the evidence right now. In practice, native speakers use both interchangeably in informal conversation.
Predictions: the key difference
| Type | Form | Why |
|---|---|---|
| "I think she'll win." | will | Based on my opinion, not visible proof. |
| "Look — she's going to win! She's way ahead." | going to | I can SEE her in the lead right now. |
Exercises
Exercise 1 — Will or Going To?
Choose the correct form and explain why.
1. "I forgot my wallet." — "Don't worry, I _____."
2. He _____ in Japan next year.
3. Careful! That tree _____ on the car!
4. I think technology _____ medicine completely.
5. "The phone is ringing." — "I _____ it."