what is the fare for a taxi ride from Guangzhou to Shenzen?

I am not sure about the fare since I do not know your specific location and destination, but I know the taxi fare will be expensive. It is costly and I think you have no need to take a taxi since the transportation between Guangzhou and Shenzhen are so convenient. You can either take bus or train between them.

its much better to take the train from guangzhou to shenzhen. 100rmb for first class. by my estimate you could be charged more than 300rmb.