Certain APIs and datasets accept or display data in Unix timestamps, which are not natively recognized by Google Sheets and can therefore not be used for calculations or other data transformations.
These timestamps can be converted as follows, substituting in your date cell where you see A1.
Convert regular date to UNIX timestamp
=(A2 - DATE(1970, 1, 1))*86400
Convert UNIX timestamp to regular date
=A2/ 86400 + DATE(1970, 1, 1)
Some UNIX timestamps are presented in milliseconds instead of seconds. In these cases you will need to divide by 1000, like this:
=(A2/1000) / 86400 + DATE(1970, 1, 1)
How to implement This code to our JSON API!
Please suggest us!.
Sorry, I don't really understand your question, can you please restate it?