A device and method for measuring a swimming pool and manufacturing a liner therefor are provided. The device includes a transducer that can be placed in the pool and configured to transmit sonic energy toward the inner surfaces of the pool. The transducer can determine relative positions of a plurality of coordinate points defined by the surfaces according to reflections of the sonic energy that are received from the surfaces. Coordinate data, which is characteristic of the positions of the coordinate points on the multiple surfaces of the pool, is stored in a memory device. The coordinate data can be used to control a liner cutting device to cut liner material to sizes corresponding to the multiple inner surfaces of the pool.