Tag question??

[mrsos]

Hello
I have a problem about tag questions.
Which one is correct?
I know it is cold, don’t I?
I know it is cold, isn’t it?
Tanks

[billmcd]

Hello
I have a problem about tag questions.
Which one is correct?
I know it is cold, don’t I? This is correct if you are looking for confirmation that you know it is cold.
I know it is cold, isn’t it? This is correct if you are looking for confirmation that the weather is cold.
Tanks

So, either could be correct depending on what agreement you are seeling.

[Raymott]

Hello
I have a problem about tag questions.
Which one is correct?
I know it is cold, don’t I?
I know it is cold, isn’t it?
Tanks

Some sentences don't take tag questions. I'd say that this is one of them.
I can't think of a context for the second. You're already agreeing that it's cold, so you wouldn't ask for further agreement in return.