Google page rank is a good indicator of website success. A higher Google page rank means that the website is more easier to find on Google search results. The page rank is updated roughly after every 3-4 months by Google. The future page rank prediction tools are used by many website owners to see how will Google rank the website on next update. The future page rank prediction tools are strictly not very accurate as they are based on estimations, however, some of the tools predictions are quite good. I am sharing a list of tools that predict Google page rank order by reliability in prediction.
Personally this is my favourite, because the prediction is very good for all my websites. It also shows if the page rank of a domain is artificially inflated. A page rank can be artificially inflated by redirecting the domain to a high page rank website. This rise in page rank is temporary because when that redirection is removed, upon next Google update, the PR again falls down. This tool also gives historical Google page rank and predicted page rank trends. Very useful for those who want to see how the PR of a website changed with time. But sometimes gives an overestimated page rank. The tool never predicts a lesser page rank. Either the predicted rank is equal to the current page rank or it is higher. This tool also displays historical page rank and predicted page rank trend.