PT. Affas Inti Selaras faced inefficiencies in managing medical equipment inventory due to reliance on manual bookkeeping and Microsoft Excel. This study developed a web-based application integrating First-In First-Out (FIFO) for perishable items and Last-In First-Out (LIFO) for non-perishable goods. The system was developed using System Development Life Cycle (SDLC) through stages of requirement analysis, UML (Unified Modeling Language) design, PHP-MySQL implementation, and black-box testing with user acceptance trials. Results demonstrated the application successfully: (1) calculated stock accurately using FIFO/LIFO algorithms, (2) generated real-time transaction reports, and (3) reduced recording discrepancies from an initial 22% to below 5% in system trials. Testing with 10 respondents yielded 82% "Good" to "Excellent" ratings, confirming operational readiness for enterprise deployment.Keywords: Inventory system; FIFO; LIFO; Warehouse management; Medical equipmentAbstrakPT. Affas Inti Selaras menghadapi ketidakefisienan dalam pengelolaan inventory alat kesehatan akibat ketergantungan pada sistem manual berbasis buku dan Microsoft Excel. Penelitian ini mengembangkan aplikasi berbasis web dengan mengintegrasikan metode First-In First-Out (FIFO) untuk barang kadaluarsa dan Last-In First-Out (LIFO) untuk barang non-kadaluarsa. Sistem dikembangkan menggunakan System Development Life Cycle (SDLC) melalui tahapan analisis kebutuhan, perancangan UML (Unified Modeling Language), implementasi dengan PHP-MySQL, serta pengujian black-box dan uji penerimaan pengguna. Hasilnya, aplikasi berhasil: (1) menghitung stok secara akurat dengan algoritma FIFO/LIFO, (2) menghasilkan laporan transaksi real-time, dan (3) mengurangi kesalahan pencatatan dari selisih awal 22% menjadi di bawah 5% berdasarkan hasil uji coba sistem. Pengujian dengan 10 responden menunjukkan 82% penilaian Baik hingga Sangat Baik, membuktikan kesiapan implementasi di lingkungan perusahaan.