Background Patient diaries and pain scales can capture the course and complications of pain managed at home in children. The Faces Pain Scale-Revised (FPS-R) is a validated scale showing reliability in children, but it has not been validated in children with sickle cell disease (SCD).Objective The purpose of this study was to evaluate comprehension and usability of an electronic modified version of the FPS-R among pediatric patients with SCD.Methods This was a cross-sectional, qualitative study involving in-person interviews with children/adolescents from the USA and their parents/legal guardians. Interviews involved cognitive debriefing and usability testing of the FPS-R.Results In total, 22 children with SCD aged 4-17 years participated. Children aged 4-6 were generally unable to demonstrate clear understanding of the FPS-R and its response scale. Overall, children aged >= 7 years understood the instrument and could complete it on the electronic device, although children aged 7-8 often needed assistance from the parent. Children aged 9-17 years were able to read and complete the instrument independently. Most participants considered the electronic device easy to use.Conclusions The FPS-R was shown to be a comprehensible and usable pain measure for children aged 7-17 with SCD and to be beneficial for future clinical studies.