With the rush of free agency over (sort of), new rumors website (which as far as I can tell, is excellently run) NFLTradeRumors.Co reports via the NFLPA that the Vikings have $11,384,009 in cap space.
The NFLPA does have completely accurate information, but as NFLTradeRumors.Co indicates, it is not necessarily up-to-date. Others may have more up-to-date information but it isn’t necessarily accurate, as it usually relies on second-hand reports of contracts and structures. The NFLPA will also be off at times because of the post-season incentives charges to the cap.
As a result, there are different cap reports, from different groups.