All casino and sports gameplay on Betcoin is played in Bitcoin, where 1 betting chip is equal to 1 mBTC. No games on Betcoin are ever played in USD or any currency other than mBTC.
1 chip = 1 mBTC = .001 BTC
If you deposit to Betcoin using a different currency, it will be converted at the current exchange rate.
When you withdraw to a different currency, it will also be converted at that rate.
Current exchange rates can be found any time by clicking on your currency of choice in the wallet deposit section of your dashboard page.