Exchanging Euro to CZK in Prague

Usually in Europe your ATM card is much better to get local currency than any other way to exchange money.
Do check the costs on the website of your bank.

The actual amount you pay per transaction depends on your contract with your bank but should be reasonable and the actual exchange is done on the paper money rate the banks use.
When you use an exchange office or bank you pay a fee which is usually higher than that of the ATM and on top of that you get an exchange rate that is worse, can be up to ten percent of the money if you go to the wrong place.
Specially those offices that do not charge a fee mostly give a very poor rate.

When we went to Prague last year, the travel agent recommended we exchange our Canadian currencies in Canada prior to departure.

Once there, we found out that the rates were better in Canada then in Prague. You can pay in Euro in most tourist places while in Prague but you have to be careful as often the waiter/clerk will do the convert in his/her head so the amount may not be exact.

Hope you enjoy the city, we did :)

The best in Prague is exchange.cz for exchange rates hands down.

However, top tip: If you need to quickly break a 10,20 euro note, any Tesco or Billa or lidl supermarket takes euros, usually at exactly the bank rate. Buy a can of coke, mars bar, etc and pay with your 10 or 20 euros- you will get back the rest in change, CZK, at the current exchange rate, and the time saved in not running round looking for an exchange is now worth the mars bar you are eating.

I am from Czech Republic, and so I can confirm that there is at least one Exchange Point on the Prague main train station. You can ask someone from Czech Railways infocenter for exact information how to find this Exchange.

Also anywhere in Czech Republic you should be able to pay directly with Euros, so you do not need any CZK.

There are exchange offices at central bus and central train station, both easy to spot. There are many more of them spread throughout the city center. Also, you can easily encounter tourist information spots, where you can get some more directions.

It is also probably good to note that some shops near the city center accept euros as currency, but the rates are usually not very good and you cannot rely on that all the shops would accept it, so it is better to have at least some CZK with you.

I don't know about the bus and train stations, but I have seen a lot exchange points in the old town, around the Charles bridge. Finding one of them should be no problem at all. But it doesn't hurt to search for some exchange offices around your hotel or the places you plan to visit.

In general banks offer better rates than exchange points, but there could be also some exception. When you have enough time just walk around the old town and compare the rates.

Last time I was in Prague, the hostel where we stayed had a strange exchange rate and it was cheaper to pay with EUR than with CZK. So sometimes is better not to exchange all the money, but to pay with Euro.

This answer gives some useful information too.

Citing from http://wikitravel.org/en/Prague#Money

In Prague, especially around tourist sights, there are plenty of Exchange offices with very bad rates which also charge commission. Best rates are found around Main Railway Station (Hlavní nádraží) - exit the station, left across the park, to street "Politických vězňů". There are about 5 offices, mostly arab-owned, and offer very good rates even for smaller amounts, and even better or negotiable for higher (over 1000 EUR, USD or such). One of the best places in the centre of the city is in Kaprova Street 14/13. Probably the best exchange rate and without commission.