PurposeThis study investigated changes in appearance due to variations in the amount of ease allowance at the bust, waist and hips with ready-made women's shirts in two different styles. The authors also examined the suitable range for ease allowance with those two styles using a sensory test for evaluating appearance.Design/methodology/approachThe authors employed two women's shirts (samples I and II) in different styles (fit and straight). The authors modified the size of the bust, waist and hips with a changeable-size dress form using 1-cm intervals. The authors observed the shape changes. With the pictures at 2-cm intervals, the authors conducted a sensory test to evaluate appearance. 20 Japanese university students in their 20s made their assessments using seven items (wrinkles, fit, silhouette, beauty, fashionable impression, comfort and purchase intention) with a five-point scale. The proportion of subjects who scored 1 or more was 40% or greater when using ease allowance in the suitable range.FindingsThe appropriate ranges of ease allowance differed according to the style and evaluation items. Regarding appearance and purchase intention with sample I from the front, the suitable range of ease allowance was 1–7 cm for the bust, 2–6 cm for the hips and 13 cm for the waist. From the side, the range was 0–6 cm for the hips and 7 cm for the bust. With sample II from the front, the suitable range of ease allowance was about 4 cm for all parts. From the side, the range was 11 cm for the bust and 4 cm for the hips.Originality/valueUsing a dress form, the authors determined suitable ranges of ease allowance for two women's shirts in fit and straight styles with seven bust, six waist and six hip sizes. The authors found that the suitable range of ease allowance varied according to the style, direction and parts of the shirt. Our results can act as a guideline for designing and selecting ease allowance for women's shirts, taking into account comfort from appearance, purchase intention and beauty.