Bangalore airport to Whitefield by Taxi: The airport taxi fare is about Rs1000 to Whitefield.
As you reach the arrival hall, agents may approach for cab services. These are expensive premium services.
If you are looking for the regular metered airport taxi, come out of the arrival hall. You'll see a row of snack stalls along the porch. Walk past them, towards your left you'll see the white airport taxis getting lined up.
Passengers are picked up on a first come first served basis. Pay to the driver at the end of the trip.
As mentioned above there are two routes to Whitefield from airport. The driver may ask you. Also the driver will ask you to pay for a toll, as you get to the highway.
It takes about 1 hour to travel between Whitefield and airport.
Bangalore airport to Whitefield by bus: Bus Route 6 operate between Whitefield and airport.Frequency is about 1 every hour. It takes about 2hours to travel from airport to Whitefield. The fare is Rs265.
Come out of the airport building and cross the passenger pickup/drip line. You'll see the bus stand. Buy ticket inside the bus.
Bus is a longish option for Bangalore. If you want to travel fast, get the taxi.