The recommended way of reaching the center form the airport is to use a train from Krakow Airport to Krakow Glowny Train Station (Krakow Main Train Station) and then a taxi. The taxi rank is located on the roof of the train station (level +1). The cost of the train ticket from the Airport to Krakow Glowny Train Station is 8 PLN (~2EUR). The cost of the taxi should not exceed 20 PLN (~5 EUR).
Another way of reaching the center from the airport is taking a taxi. Its cost should not exceed 30 EUR (see Krakow Airport Taxi Service). You can hire cheaper taxi, we recommend BARBAKAN taxi (~ 15 EUR) available at +48 12 196 61 and +48 (0) 800 400 400 or ICAR taxi (~ 10 EUR) available at +48 12 653 55 55. The taxi rank is just outside the terminal.
The third option of reaching the center is to use a train from Krakow Airport to Krakow Glowny Train Station and then a public transport (a bus or a tram).
It is also possible to take a 292 bus from the airport to the city centre. However, it has many stops, so the journey is quite long.
More information can be found here.