What is the difference between 刚刚 and 刚才 in Mandarin? Both words express the meaning &quot;just&quot; or &quot;just now&quot; in time. For example,

我刚刚回家了。
我刚刚吃饭了。

In these cases, should I use 刚刚 or 刚才? Is there any difference and/or which one sounds more natural?
Both means the same, but which one sounds more natural depends on what the questioner uses.

if they ask: 

你刚刚去哪了？

you answer with: 

我刚刚回家了。

if they ask: 

你刚才去哪了？ 

you answer with: 

我刚才回家了。

Of course, it's not wrong to answer 刚刚 with 刚才, it's not that big of a deal, both works, just a matter of preference really.