Wikipedia
DNPric.es
DNPric.es (pronounced as "Di eN Prices" for "Domain Name Prices", also known as DNSal.es) is an online service that provides access to a database of historic data of Internet asset sales, i.e., domain names and web sites. It contains the deals made in the secondary markets as well as premium sales from the TLDs. As of 2016 it is the most complete public database of domain name sales online with past records of over a million domain names. It has an extended statistical section allowing to analyse the data from many angles, time, brokers, length, etcetera.