This document is Neural Network-based Video Coding 3 (NNVC 3) software algorithm description. It includes the coding features and encoding methods implemented in NNVC-3.0 software that are under coordinated exploration study by the Joint Video Exploration Team (JVET) of ITU-T VCEG and ISO/IEC MPEG as potential neural network video coding technology beyond the capabilities of VVC. The groups are working together on this exploration activity in a joint collaboration effort known as the Joint Video Exploration Team (JVET) to evaluate compression technology designs proposed by their experts in this area.