To adress the problem of static power consumption, approaches as ABB and AVS have been proposed to reduce runtime leakage in integrated circuits. Applying these techniques is a trade off between power and delay, which is best decided early in the design flow. Therefore high level power and delay estimation is needed. In our work, we present a fast RT Level delay macro model considering supply and bias voltages and temperature. Errors below 5% combined with only few characterization data enables this approach to be used by high level design tools to support leakage optimization by e.g. ABB and AVS.