If the calendar you are using on both devices is actually the Google Calender (which is standard for most Android devices), then you can easily set them to sync to your google account. Both would have to be accessing the same account though for this to work.
Actually Sanding phones come with the Samsung calendar so downloaded the the Google Calendar and inclicked my Samsung email address and clicked my Google email address on both my phone amd tablet but they are still not syncing. Thanks anyway.