With Poker Equity Calculator you can calculate the probability of winning a Texas Holdem hand.
It works in a similar way to PokerStove, Pokerstrategy Equilator or Equilab.

You can put your opponents into a range, or select specific cards. You can specify the Flop, Turn and/or River cards.

Equity calculation is done with Monte Carlo simulation.
In some seconds you will get a good estimation of the probability of winning.