The best month to fly between Guangzhou and Shanghai is April and the most expensive month to fly is June. (Average prices, based on 1304 datapoints.)
The cheapest airline flying from Guangzhou to Shanghai is China Eastern Airlines. They are 27% cheaper than China Southern Airlines. (Average prices, based on 1318 datapoints.)
The best time to fly is at around 6. (Average prices, based on 1335 datapoints.)