One carbon calculator is the one created by the EPA, linked here. (However it does not include air travel. Here's one calculator that handles air flights and here's a good article on the variation among flight emission calculators.)
There are many, many more; they generally take several minutes to work through.
Below are search results from Google for a variety of carbon footprint calculators. We recommend you try more than one and compare results, as there is a wide variety of formulas they each use. (For example, how they calculate CO2 equivalents.)
(Sorry for the width of the box, that's Google's minimum box width.)