One of the difficult thing to calculate while traveling internationally is the price you are actually paying in your home currency when you shop or eat. When you give a £10 bill, your mind may be saying $10 to you, whereas you are actually spending 1.5 times. Even shopping for artifacts may not make things easier with all the numbers in your mind.
Consider keeping a currency converter cheat-sheet in your wallet for easy and quick conversions. The OANDA Currency Cheat Sheet for Travelers makes it really simple to print one. Just select your home and destination currencies, the kind of rate you’re looking at and the website will give you a table of side-by-side comparison of the values.
Next steps – print, cut and save it in your wallet, making it an easy reference to know your spending. You can laminate it or just apply some clear tape to prevent it from wear and tear.