Penelitian ini bertujuan untuk mengetahui kelayakan software pendeteksi dan pereduksi miskonsepsi pada materi stokiometri yang ditinjau dari validitas, kepraktisan, dan keefektifannya. Validitas software dinilai dari dua aspek yaitu validitas isi dan konstruk sedangkan kepraktisan software dinilai dari hasil respon peserta didik didukung oleh hasil observasi aktivitas peserta didik dan keefektifan software dinilai dari pergeseran konsepsi dari miskonsepsi (M) menjadi paham konsep (PK). Penelitian ini menggunakan metode Research and Development (R&D) pada 15 peserta didik di SMA Negeri 1 Gedangan yang mengalami miskonsepsi dengan persentase tertinggi. Hasil dari penelitian ini menunjukkan bahwa software yang dikembangkan layak digunakan dengan persentase validitas isi sebesar 85,37% (sangat valid) dan validitas konstruk sebesar 85,55% (sangat valid), kepraktisan sebesar 81,92% (sangat praktis), dan keefektifan sebesar 80,55% (sangat efektif).

This study aims to know the feasibility of software to detect and reduce misconception in the stochiometry material based on its validity, practicality, and effectiveness. The validity of software is assesed from two aspects that are content and construct validity while the practicality of software is assesed from the results of student’s responses which are supported by the results of observation of student’s activities and the effectiveness of software is assesed from the conception shift from misconception to understand the concept. This study uses Research and Development (R&D) method. The subjects of this study are 15 student of SMA Negeri 1 Gedangan who have the high misconception percentage. The result of this study shows that software is feasible which is proved by the precentage of content validity about 85,37% (categorized as valid), the percentage of construct validity about 85,55% (categorized as valid), the percentage of practicality about 81,92% (categorized as practice), and the percentage of effectiveness about 80,55% (categorized as effective).