Running robots at insect scale are an upcoming research field, because of their numerous potential applications like exploration of hazardous environments such as collapsed buildings, natural disaster sites and debris. To date no report exists on such a robot that either exploits its resonance, or that is monolithic. These properties, however, could improve the performance of these robotic insects in terms of efficiency, actuation complexity, manufacturing tolerance, suitability for rapid prototyping, large number reproduction and miniaturization. This article presents the monolithic design of FARbot; a Frequency Actuated Resonant robot that uses resonance to increase its stride length and consists of one single piece. To achieve the design of FARbot a novel design methodology is presented and utilized to systematically obtain the necessary compliant mechanism that resonates in a desired motion and at a desired frequency. The final design has been manufactured monolithically from the material HTM140-V2 using digital light processing 3D-printing technology. In terms of production time FARbot outperforms all other robots in this research field. An earlier produced, non-monolithic prototype shows resonance at the desired eigenfrequency at which its stride length is amplified by a maximum factor of 22.74 for constant energy demand. This proves the benefit of using resonance and also validates the proposed design methodology.