I'm just kidding.

我只是在开玩笑。

《柯林斯英汉双解大词典》

I'm just kidding. Yes, you can.

好吧，如果我玩“三人行”你不能参加。

youdao

I'm just kidding, Muumuu!

我只是开玩笑，穆穆！

youdao

If there's no New Orleans left the - and I'm just kidding, Lord.

NPR: New Orleans Family Heads North

I'm sure there's -- gosh, people just pulled down their blog posts on -- no, I'm kidding.

WHITEHOUSE: Press Briefing