Aspects described herein relate to mask synthesis using design guided offsets. A target shape on an image surface to be fabricated using a mask based on a design of an integrated circuit is obtained. Rays are generated emanating from respective anchor points. The anchor points are on a boundary of the target shape or a boundary of a mask shape of the mask. For each ray of the rays, a distance is defined between a first intersection of the respective ray and the boundary of the target shape and a second intersection of the respective ray and the boundary of the mask shape. An analysis is performed by one or more processors, where the analysis is configured to modify the distances based on an error between the target shape and a resulting shape simulated to be on the image surface resulting from the mask shape.