Subscribe to our newsletter:

Rational Exchange

iPhone / iPad
  • Travel
  • Finance
I want this app
Download from AppStore

"How much would they charge me back home?"

Rational Exchange is the easiest way to figure out what something would cost where you're from, including tax and tip.

Featuring tax and tipping customs from hundreds of countries, quickly determine the price tag you'd see back home, considering how you'd be charged both where you're visiting, and where you're from.

Use Rational Exchange wherever you're traveling, with or without a data plan – we save everything for offline use.

Use Rational Exchange to find out:

* What you'd be charged at home
* Tipping customs
* Any Added Tax
* Your total cost in both your home and foreign currencies

Rational Exchange will fetch the latest exchange rates, tax and tipping info whenever your device has an internet connection.


A quick example!

A beer in Norway costs 96 NOK. A straight exchange rate would be $14.22, but they tip 10% and don't add tax to the price, so the total would be NOK105.60, or $15.51 USD.

In Texas, we do things a little differently: the same $15.51 total would be broken down as a $12.59 price tag for the beer, $1.89 for a 15% tip, and $1.03 as the 8.15% added tax. To make it easy, Rational Exchange will round that price tag to "$12.50" back home.

Yes, the beer's still expensive compared to back home, but at least you know what a beer in Texas with Norwegian prices would look like, all in. Plus, you know what to tip, and what to expect!


We'll never ask you to rate us, so please leave a review if you like it! If you have an update to tax and tip customs, email us at

If you have any questions or suggestions, get in touch at