InterviewSkool is an interview-practice platform that uses an AI interviewer, Alex, to help software engineers prepare for technical hiring processes. It offers two practice tracks: coding interviews focused on data structures and algorithms, and system design interviews conducted on an interactive whiteboard. In coding sessions, users solve problems in a supported programming language while Alex asks follow-up questions about their reasoning, complexity, and possible improvements. System design practice covers requirements, architecture, and deeper design decisions, with candidates explaining and defending their choices.

Users can select a company and experience level, from SDE-1 through senior and staff roles, and practice questions sourced from interviews at 31 companies. Coding sessions include live code execution and hidden test suites; system design sessions assess decisions across individual parameters. After each interview, users receive feedback and a hiring signal, with reports covering readiness, strengths, and areas to improve. InterviewSkool also provides a free demo that does not require a credit card.