International Journal of Neutrosophic Science IJNS 2690-6805 2692-6148 10.54216/IJNS https://www.americaspg.com/journals/show/2868 2020 2020 Department of Mathematics, Little Flower College-680103, Guruvayoor, India. admin admin Department of Mathematics and Physics, College of Engineering, Australian University, West Mishref, Safat 13015, Kuwait. Sadeq Damrah Zayed Military College, Department of General Science, UAE. Mutaz M. Abbas Ali Department of Mathematics, Faculty of Science and Technology, Irbid National University, P.O. Box: 2600 Irbid, Jordan Abdallah Al Al-Husban Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu 602105, India M. Palanikumar We describe certain operations and present the theory of the Type-I extension Diophantine neutrosophic interval valued soft set. Additionally, we go over an algorithm that uses the Type-I soft set model to address the decision-making problem. We present a similarity measure between two Type-I extension Diophantine neutrosophic interval valued soft sets and talk about how it might be used in practical applications. A few exemplary cases are provided to demonstrate their practical application in solving uncertain problems. 2024 2024 151 164 10.54216/IJNS.240411 https://www.americaspg.com/articleinfo/21/show/2868