You can’t get by without money, right? Nothing like a little practical language learning…
For starters, the words “money” and “currency” can both be translated as پول (pūl).
Now for specific currencies. This is easier for Persian than, say, Arabic, because when we talking about the Persian-speaking world we’re dealing basically with the currency of Iran (ایران), or maybe Iran and Tajikistan (تاجیکِستان or Тоҷикистон), or Iran, Tajikistan, and Afghanistan (افغانِستان). Yes, Afghanistan, which has historically been part of “Greater Iran” and where a dialect of Persian called Dari, دَری, is one of the two official languages (and is actually more widely spoken than the other, Pashto). So at most you’re dealing with maybe three countries, as opposed to all the countries, with all their various currencies, in the Arabic-speaking world. Iran uses the ریال (riyāl, or “rial” according to the official Latin transliteration). This is derived from the Spanish real, a now-obsolete currency from the 14th-19th centuries that gave its name to several currencies in the Middle East, particularly in the Persian/Arabian Gulf region and then into Iran, briefly from 1798-1825 and then from 1932 through today. The rial is divided (like cents to our dollar) into 100 دینار (dīnār), a term that is also (somewhat confusingly) used in many Arab countries either as the main currency or, as here, as the subdivision of the main currency. This word hails all the way back to the original Islamic currency, the gold dinar, which derived from the Roman/Byzantine denarius.
Here’s the thing about the rial, though; thanks to runaway inflation caused in part by Western economic sanctions (hooray us!), it’s actually the least-valued currency in the world. Even Iranians don’t like to talk in terms of rial, so they will often refer to the تومان (tūmān, or “toman”). This was at one time the main currency of Iran (in fact, when the rial was first introduced in that 1798-1825 period, it was as a subdivision of the toman. It’s not an official currency anymore, having been replaced by the rial in 1932 at the rate of 10 rials per toman, but it is still used informally to mean “10 rials.” I guess quoting a price of “1000 toman” sounds less depressing than “10,000 rials.” Which, by the way, is worth anywhere from about a quarter to just under a dollar depending on the exchange rate you’re using (hooray us!). The word “toman” comes from a Mongolian word, tümen, which means “unit of 10,000,” because when it was introduced it was worth 10,000 dinar.
This means that, even though the rial is the official currency, if you want to ask somebody how much something costs you’d probably be better off using toman. Actually, you’re best off just gesturing to what you want and saying چَنده؟ (chandah, “chandeh”), which just means “how much (is it)?” But if you must mention currency, چَند تومان است؟ (chand tūmān ast, “how much is it”) or چَند تومان این است؟ (chand tūmān īn ast, “how much is this”) is the way to go. Or, if your vocabulary is good enough, replace این with the specific thing you’re asking about.
In Tajikistan you’ll be using the cомонӣ (somoni, and oh by the way Tajik is still written in a modified Cyrillic alphabet, and not coincidentally this may be the first and last time I mention Tajik on this blog). The somoni is named for the “father of Tajikistan, Ismail Samani, the founder of the 9th-10th century Samanid Dynasty that ruled much of modern Iran and Central Asia during its heyday. The somoni is divided into 100 дирам (diram), which is the name of various currencies in the Arab world as well and is derived from the Greek δραχμή (drachma).
The currency in Afghanistan is the افغانی (afghānī), which makes sense, and is subdivided into…wait for it…100 پول (pūl), and now we’ve come full circle and I’m done.