The difference between thanks and thank you?

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hello,
Is that correct to use thank you in informal way and thanks in formal way ?
What is the difference between thanks and thank you ?

2

Thank you = not very formal but not informal
Thanks = informal

These two don’t have difference in meaning if used to say “I appreciate what you did”.
It is just that “thanks” is an interjection which is used to say “thank you”

We can also use these two as follows:

Thank you. = idiom used interjectionally ex. Thank you!
= noun ex. I didn’t even get a thank you after helping him.
= adjective ex. I sent them a thank you note.

Thanks. = interjection ex. Thanks!
= noun ex. Give them our thanks.
= idiom “thanks to” (because of) ex. Thanks to him, we were able to finish the project.

3

Both are the same.

Thanks Jcbabo
Thank you very much.