Using the exchange rate on this site....http://www.xe.com/ucc/
The US Open singles winners cheque is actually the 2nd biggest of the Slams, with the Australian Open being the most generous slam in term of prizemoney to the winner when historically the AO was considered the "poor man's slam"
. It is also interesting considering the US Open is historically considered to gave out the most money. Funnier still Wimbledon gives out the least amount of money to the winner of the lot!
2009 Prizemoney (from the official website in their own currency)
Australian Open: AU$2,000,000
Roland Garros: EU$1,060,000
US Open: US$1,600,000
after conversion (to US$)
1. Australian Open: US$1,726,637
2. US Open: US$1,600,000
3. Roland Garros: US$1,546,974
4. Wimbledon: US1,418,819