Simple Arbitrage is the price difference of the same trading pair on exactly two different exchanges.
The table on this page gives you the best real-time opportunities across all exchanges we track. No trading fees are included, so you should subtract them from what is shown. Opportunities are refreshed every 10 seconds. Orange labels indicate that you have an account on one of the exchanges involved. Green label indicates that you have an account on both exchanges.
You can conveniently add a Price Difference robot by clicking on the Add link next to each opportunity. It will open and prepopulate the form to add the robot, which you can also edit before submitting.