Background. Currently, anthropometry measurement is considered as an important tool to detect stunted children. Manual measurements of anthropometric tools are commonly used due to their simplicity. However, manual anthropometric techniques produce issues related to human measurement errors. Objectives. The purpose of the study was to perform a precision and accuracy test for a manually modified length board and to assess the prevalence of stunting. Methods. This study was an observational study to assess the precision and accuracy of 360 children's height measurements taken by caders and facilitators as the gold standard. A total of 60 Posyandu caders and 180 children under five year were recruited from three locations of studies; Bakaran Batu in Deli Serdang District, Sidorame Barat in Medan City, and Sidagal in Tapanuli Utara District. The formula for precision and accuracy tests was provided to run automatically calculation. Results. A total of 83.3% of caders had good precision and accuracy in using the length board as a height measurement tool. Regular trainings resulted in more caders having better accuracy and precision skills. Conclusion. A modified length board can be an alternative manual height measurement at the community level and to be used for door-to-door survey.