This article aims to develop a precision methodology, to evaluate the work of a helical doser from a seed planter. The experiment was carried out in two conditions, a bench in laboratory, and, in a seed planter in the field, comparing the proposed evaluation methodology in the laboratory, linear methodology (LM), against the ISO 5690/2 (1984) method. In the laboratory's test, it was tested: 0°, +11° and -11° slope of doser. In LM, it was used a metal gutter with 125 polyethylene collectors, both placed next to the other. In the field, it was used only LM, and for such two doses were tested, 250 and 440kg ha -1 . The variation coefficient (VC) in the LM, the 0º condition performed with the best dosage, varying from 10.15% to 13.76%, against 13.95% to 17.84% in the + 11° slope and 11.86% to 13.79% in the -11º. The VC compared in ISO 5690/2 method shows a very different Rosa et al.; JEAI, 31(5): 1-7, 2019; Article no.JEAI.46242 2 result, indicating variations from 0.7 to 2.3%, which is 88% smaller than LM. In field, the VC increased to 25.70% to 40.96%. Comparing the VC of ISO 5690/2 with the field test, the differences are even bigger, 2.3% compared to 40.96%. The LM presents concise data to clearly observe variations in the working conditions of the fertilizer helical doser. Method Article