Unfortunately the picture is low resolution and it is difficult to see the wires and connector letters. If possible send a higher resolution picture, or if not, send a list of what wire is connected to what terminal. For example:
G - Green
W - White
C - Blue
(for each connected wire)
You can also just check yourself using the Compatibility Checker.
Thanks for answering, sporfrog.
@amore288, welcome to the Google Nest Community and thanks for posting. Do you still need help with this? If yes, please provide another photo of your thermostat wires as the one you've posted above is a bit blurry and we can't identify the labels. Also, what is the make and model of your old thermostat and what type of HVAC system do you have?