A circuit design method, computer program product and chip design system embodying the method. A gate selected for static timing analysis (STA) from a circuit design. Initial performance characteristics (e.g., load and transition slew) are determined for the selected gate. A charge equivalent effective capacitance (CQeff) is determined for the gate from the initial performance characteristics. A gate delay is determined in a single pass for the gate using CQeff as an effective load for said selected gate. Optionally, if the total gate load capacitance (Ctot) exceeds CQeff by less than a minimum, the effective capacitance (Ceff) is determined and used for determining the gate delay instead.