Use this BAC calculator to see approximately how many drinks it would take for you to reach different levels of impairment. Here is how to use it: On the left, just enter your weight and choose your gender. Then under “Drink Details”, select your drink of choice and click “CREATE”. You’ll notice to the right on the timescale grid, it displays the drink you selected. You can use your mouse to drag the drinks around to different times to see how it affects the BAC over time by looking at the line chart below. Select a few more drinks and drag them around on different times to see how fast it affects your BAC. I think you'll be SURPRISED how fast it increases with each drink you have.