The development of information and communication technologies has created limitless prospects for using augmented reality (AR) in various fields. Unfortunately, the multitasking nature of AR systems prevents learners from successfully reflecting and retaining knowledge. This study developed and designed a learning analytics dashboard (LAD) with three components: personal learning data, social comparison, and visualization of the learning process, to promote knowledge acquisition and metacognitive awareness among AR learners. A total of 31 intermediate-level Japanese learners participated in an experiment involving pre-tests, post-tests, and a delayed test to assess the LAD. Learners engaged with the AR learning system for Japanese compound verb learning and utilized the LAD to monitor and reflect on their AR learning activities. Behavioral data were analyzed using Lag Sequential Analysis (LSA), while learning performance was evaluated through one-way repeated-measures ANOVA tests. The findings indicate that the use of the LAD significantly improves learning outcomes and metacognitive processes, such as knowledge of cognition and regulation of cognition. Additionally, there were different usage patterns of the dashboard among learners, which corresponded to significant differences in their learning outcomes and changes in metacognitive awareness. Learners who primarily focused on the learning process and social comparison components of the dashboard demonstrated improved knowledge retention. Conversely, those who mainly concentrated on personal learning data experienced the most significant gains in metacognitive awareness. This study also provides crucial design insights on the integration of dashboard components with cognitive efforts to maximize learning outcomes.