Price check: rental, taxi, or Uber ... what's cheaper?

Hiring a rental car for a round trip from Auckland city to the airport would be 386 per cent cheaper than a taxi.

Research from rental car company GO Rentals pitted the costs of Ubers, taxis and rental cars across major city centres around the world and found a rented car often comes out much cheaper - but that's only if you exclude the cost of parking and petrol.

"There are multiple variables which must be considered when choosing how to get around and which will influence the final cost and convenience," said GO Rentals general manager James Dalglish.

"And more than that, the absolute cost also depends quite strongly on just precisely where in the world you are," he said.

The Italian city of Milan was the most cost-effective place to grab a rental car over a taxi or Uber, GO Rentals research found, where a return taxi ride can set you back $243.50. Uber fares even worse at $282.9. A rental car, on the other hand, costs $40.74 for a day, a 500 per cent difference in price.

Uber wasn't always cheaper than a taxi in some parts of the world. Another Italian city, Rome, taxi fares were $75.79, compared to Uber fares of $88.94.

The most pronounced disparity was in Dublin, Ireland where an Uber to the airport cost over $20 more than a taxi. Other cities where you're better of in a taxi rather than an Uber included Cairo, Dubai, Mumbai, Mexico City, Helsinki, Madrid, and Tokyo.

However, Uber was typically a much cheaper option. In Birmingham, England, it cost 163 per cent more to take a taxi over an Uber. Los Angeles, Las Vegas, Prague and London all sported Uber fares which were more than half the cost of a taxi.

Renting a car wasn't always the best option either, with a one-day rental costing $201.43 in Hong Kong, $151.73 in Oslo and $139.94 in Zurich.