The ride from DXB Airport to Burj Khalifa- Dubai Mall Metro Station lasts around 25 minutes. You'll also need a Nol Card to pay for your subway ticket. Hence, if you buy a Red Ticket, you'll pay 6 AED(1.50€/1.50$), while if you settle on a Silver Card, your ticket will cost 5 AED(1.26€/1.26$).