The KM3NeT neutrino detectors are currently under construction at two locations in the Mediterranean Sea, aiming to detect the Cherenkov light generated by high-energy relativistic charged particles in seawater. The KM3NeT collaboration will produce scientific data valuable both for the astrophysics and neutrino physics communities as well as for the Earth and Sea science community. An Open Science Portal and infrastructure are under development to provide public access to open KM3NeT data, software and services. In this contribution, the current architecture, interfaces and usage examples are presented.