This Google Pagerank prediction tool will predict your website's future Page Rank based on the quality and quantity of backlinks. Note, PR predictor will provide an estimation of the future Google PageRank and should not be considered exact.
Really, it is not the Google Pagerank prediction this is detecting of Real PR. There is no secret that Google shows not real pr. Current PR is usually lower than must be. It could be because your site is young or you are selling links. You can also violate some google rules without knowing about existence of these norms. Therefore, generally, Real PR must be higher than current pagerank on your google toolbar. Pagerank prediction tool shows Real PR without any Google's reducing factors.
So visit the link My Blog Future Page Rank to check your Page Rank.