A method and apparatus for PCB layout of a circuit simulated over a network is provided. Techniques are provided for designing a circuit that satisfies user-specified functional requirements received over a network. Based on the specified requirements, components and a topology for constructing the circuit are automatically determined. The components determined during this operation have operational values such that, when the components are arranged according to the topology to form the circuit, the circuit satisfies the user-specified functional requirements. The components are placed on a PC board having landing areas designed to accommodate all of the anticipated component sizes for the type of circuit being designed. The PC board may be cropped to the desired size. The PCB may be cropped automatically or manually by the user. The component and topology information may be used to generate a schematic diagram that is delivered in a web page to the user over the network. The user may thermally and electrically simulate the designed circuit. Many characteristics of the PC board may be adjusted to produce an accurate circuit.