Hello,
What is the difference or which one is best For clock calendar?
DS1307 or HT1380??

 

I think you meant HT1380
and read the datasheets for each chip and decide which on is "best" for your application..
http://datasheets.maximintegrated.com/en/ds/DS1307.pdf
http://www.holtek.com/pdf/consumer/ht1380_1v130.pdf

 

I think you meant HT1380
and read the datasheets for each chip and decide which on is "best" for your application..

Yes.
Both are same on I2C communication.

 

"Best" depends completely on *your* application. We don't know what you are trying to design and build, so there is no evaluation.

ak