<![CDATA[Previously, all sales transactions at Mahmud Racing Apparel were managed manually through social media, leading to difficulties in data tracking, high susceptibility to recording errors, and delays in compiling sales reports. To address these challenges, this research centers on the design and engineering of a digital data management platform utilizing the Rapid Application Development (RAD) approach, alongside functional verification and the System Usability Scale (SUS) framework. All planned testing cases were accomplished with zero average SUS score reached 82, which is classified as "excellent," and the duration of each observed operational activity became significantly shorter, with the greatest time savings found in order data retrieval (77.78%) and sales report compilation (72.22%). These outcomes underscore how the engineered platform stands as exceptionally practical in daily operations, while actively contributes to fostering MSME digitalization in the custom apparel sector.Keyywords: Online sales management system; Rapid Application Development; System Usability Scale; operational efficiency; MSMEs AbstrakSebelumnya, seluruh transaksi penjualan di Mahmud Racing Apparel dikelola secara manual melalui media sosial, sehingga memicu kendala dalam pelacakan data, rentan terhadap kesalahan pencatatan, serta keterlambatan dalam penyusunan laporan penjualan. Guna mengatasi kendala tersebut, penelitian ini menitikberatkan pada perancangan dan pembangunan platform digital manajemen data lewat pendekatan Rapid Application Development (RAD), pengujian fungsionalitas, serta instrumen System Usability Scale (SUS). Seluruh skenario pengujian yang direncanakan berhasil diselesaikan tanpa kesalahan, dengan skor rata-rata SUS mencapai 82 yang diklasifikasikan sebagai "sangat baik" (excellent). Selain itu, durasi dari setiap aktivitas operasional yang diamati menjadi jauh lebih singkat, di mana penghematan waktu paling signifikan ditemukan pada penarikan data pesanan (77,78%) dan penyusunan laporan penjualan (72,22%). Temuan ini memperkokoh bahwasanya platform yang dibangun berdiri sebagai solusi yang sangat praktis dalam operasional sehari-hari, sekaligus berkontribusi aktif dalam mendorong digitalisasi UMKM di sektor konveksi kustom. ]]>
