Depends on which account type you are talking about. Fxcess has two account options to choose from, the Classic and the ECN account type. The first one comes with a flexible leverage up to 1:1000, and the second one with 1:500. In both cases, this leverage ratio is quite generous.
Trading with a large leverage is considered risky, and if you are not an experienced trader and are still in the process of improving your risk-management strategy, I would advise you to trade with a low leverage. I trade with a 1:200 ratio. Even this amount is considered relatively high by conservative traders but with the size of my account, which is not significant, with this leverage, I can build up my account and make decent profits.