Traditional methods of assessing listening skills in language learners suffer from drawbacks such as subjectivity, inconsistency, and time-intensive grading processes. To overcome these limitations, we introduce an innovative assessment instrument designed to efficiently and effectively evaluate students' listening skills while offering instructors a dependable means to track progress. This study proposes the development of an online assessment instrument tailored to measure language learners' comprehension of spoken language. The two instruments incorporate a questionnaire and a variety of question formats, each gauging students' grasp of spoken discourse across diverse contexts and accents. Additionally, the online assessment assesses their proficiency in identifying main ideas, supporting details, and inferred implications within spoken communication. Accessible through a dedicated learning management system (LMS) platform available at http://lms.elsida.ac.id/, this instrument empowers instructors with a robust mechanism to gauge their students' advancement. By providing a thorough assessment of listening skills, the instrument stands as a powerful resource for educators seeking to drive ongoing improvement. The study's findings highlight how this assessment instrument can improve language learning through ongoing feedback. Through ongoing enhancements and testing in language learning contexts, the instrument contributes to a more effective evaluation of listening skills in language education.