It’s one of the oddities of modern travel: once you calculate the time spent getting to the airport and going through security, a quick flight can easily end up taking more time than a long drive. But what about the cost of it all?
TravelMath—a search engine that answers all sorts of numbers-related questions about travel—just introduced a new feature to help travelers figure out exactly and definitively whether it’s better to fly or drive.
The website has always provided information about the exact time differences between flying (including check-in and security times) and driving, but now it has launched a side-by-side comparison with pros and cons—some of which often go unconsidered.
While driving is usually cheaper, it may also require taking time off of work. TravelMath figures the cost of time off and figure that into its decision. For those who are ecologically conscious, the search engine will determine which form of transportation will leave a smaller carbon footprint. The one thing it won’t calculate is time spent stalled in traffic, which could be a deal breaker for some routes.
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At the end of the calculations, TravelMath assigns a score to each contender. The one with the lowest score is that which makes more sense all around. In the case that the two scores are fairly close, TravelMath will tell users to “choose either option based on your specific needs.”
For those debating how they’re going to get home this holiday season, TravelMath could be an excellent starting point. Just remember: The site won’t figure in any time spent last-minute present shopping in Duty Free.
This article originally appeared on TravelandLeisure.com.