Understand that in some cultures, direct disbelief might seem rude. 'You're kidding' can soften the impression.

Cultural Nuance

Your tone can change the meaning from surprise to sarcasm, so match it with the situation.

Emotional Range

Adding 'right?' at the end can invite the other person to confirm the unbelievable news.

The phrase can express frustration in a lighter, less confrontational way.

It's typically used among peers or friends rather than in formal situations.

Use it to convey your happiness about someone's good news, as it shows enthusiasm.

The phrase can signal that you are pleasantly taken aback by good news.