Well, I'm not sure how useful calibration would be, given the massive diversion in viewing platforms and the lack of standards for the web.
Generally a big reason for colour correction is to meet certain boundaries required for broadcast. This is because it used to be (and probably is, in some small places) that illegal luma and colours could actually knock the transmission off air. These days most places have clippers which will stop this happening, but there are still rules to abide by.
Inside these extremes you can go just about anywhere you want. You want everyone's skin to be green? Fine. That's a creative decision. So. I guess what I'm saying is, there isn't really a standard. Since your output will be on computer screens, grade for computer screens - not an external broadcast monitor. And test your output on a PC as well as a Mac. PCs are 10% darker than Macs.