Kaizena's product is a Google Docs and Google Drive add-on that teachers use to deliver audio, written, and skills-based feedback on student assignments. It replaces cramped margin notes with voice comments and lets educators build reusable comment libraries and custom rubric-like skills to track specific competencies. The tool is also available as a Chrome extension.

The primary users are K-12 and higher-ed teachers and their students, who exchange feedback inside documents rather than on separate platforms. Kaizena competes in the edtech and classroom-assessment software category alongside other feedback, grading, and learning-management tools. It has historically positioned itself as a low-cost, versatile add-on for educators who want more extensive and varied feedback than plain text comments allow.