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Range scientists are interested in patterns of livestock use within grazed units, especially when forage resources are spatially heterogeneous. Quantifying space use is particularly important when research hypotheses or management plans predict specific patterns of resource selection. Direct observation of livestock is costly and time-consuming, and indirect measures are temporally imprecise, represent only samples of possible locations, and require worker hours to measure. Several commercial solutions based on Global Positioning System (GPS) technology fit animals with GPS receivers that record their location at programmed intervals, but the cost is often prohibitive. We designed our own solution around a low-cost, open-source microcontroller based on the Arduino system. Hardware includes a microcontroller and microSD card logger, GPS receiver, and lithium-poly battery. The system is programmed in C/C++ with templates freely available from the manufacturer. All software is open-source and user-customizable. We sealed the loggers in small rubberized plastic cases and strapped them to cattle and sheep at the Hettinger Research Extension Center in Hettinger, ND. The whole livestock-ready apparatus cost approximately $125 per unit. Through the summer of 2017 we had approximately three dozen successful one-week deployments, with no equipment loss and only minor damage we learned to prevent. In addition to presenting the system, we also discuss data analysis to offer insight into the number of units and logging frequencies required of livestock GPS monitoring, regardless of system used. We ran three units per pasture logging at 20-second intervals, and analyze these data with respect to minimum number of units needed to estimate herd behavior and optimum logging patterns to infer behavior and extend battery life. Although power demands remain a limitation and priority for further development, our system is a viable solution for short-duration deployment on experimental rangelands with livestock handling facilities.