The crosslink density is an important property affecting the major characteristics of cured rubber. A comparison between the crosslink density calculations by different methods Rheometric, Swelling and Mooney-Rivlin methods for cured NR (natural rubber), SBR (styrene-butadiene rubber), NBR (nitrile rubber) and their blends were discussed. The obtained data by different comparison methods showed a very near results to each other. The best method among the three used methods for obtaining these results is the Mooney-Rivlin equation, due to its simple and reliable method for determination of crosslink density for cured rubber. Also, it is considered as an environmentally accepted method, since it depends on calculations and not using any hazardous solvents or chemicals.