Iran’s official currency is Iranian Rial, but everywhere the currency people use is Tomans. In a simple scenario, 1 Toman = 10 Rials. So far so good, but things get confusing when number of zeros increase. If for example a taxi driver shows you 3 fingers, it means means he wants 3000 Tomans = 30,000 Rials.
After my first couple of days in Iran, I concluded when the price is within two digits, then one has to multiply it by 10 thousands to get the exact amount in Rials. If the price is in more than two digits then it should be multiplied with 10.
But things do get twisted in reality.
Today a taxi driver showed me 5 fingers for a very short ride, I understood that he meant 500 Tomans = 5000 Rials, and not 5000 Tomans (according to my rule of thumb). One the way back, another taxi driver showed me 5 fingers and I sat in, thinking I have to pay the same amount. But it turned out he wanted 5000 Tomans = 50,000 Rials. 10 times more than I paid the other way. I threatened to call the police but still I had to shell out 30,000 Rials.
I am still learning what the hell a Toman is, and how to count such big numbers in my head. Practically I think three zeros from the Iranian currency can be discarded. As an reference, a small bottle of mineral water costs 5000 Rials.
In the photo you see the currency notes of:
50,000 Rials (being the most useful note)