The cooling for data center becomes more and more challenging as the silicon power increases significantly. Liquid cooling would be one of the solutions to meet the upcoming high power demand, while maintaining high cooling efficiency. A standalone rack level liquid cooling is one of the liquid cooling solution with high flexibility and requests no data center infrastructure change. In this solution, the heat from high power components is transferred by coolant from cold plate to the rear door heat exchanger, and then the heat is finally rejected by air. The other lower power components are cooled by air. For hardware, the design of key elements will be standardized and compatible to ORV3 and 19” rack. For software, rack management software will base on Redfish schemas to develop for interoperability and cooling efficiency optimization at run-time by continuously adjusting liquid flow speed, output of rear fan door, and fan speed of individual computer systems. It could be deployed to the existing data centers without any facility change as an interim, efficiency solution before the deployment with facility coolant. In this presentation, Wiwynn and Facebook will co-present the standalone rack level liquid cooling solution.