Riiid (Santa)
AI test prep, best known for TOEIC
Independence: Addestra builds learning products too (MathsTutor, TinkerWell). We never review or score our own, and no tool pays to be listed or to rank higher — how we assess fit.
What it does
What the AI actually does — Knowledge-tracing deep-learning models estimate what a learner knows from answer history and serve the next question predicted to most raise their score; open-sourced the EdNet dataset (~131M interactions).
Why it was built — Use knowledge-tracing AI to hit a target score with the fewest questions, then generalise the engine to other exams.
Who built it
- Company
- Riiid Labs, Inc.
- Founders
- YJ Jang · Jaewe Heo · Minsung Noh
- HQ / origin
- Seoul, South Korea
- Founded
- 2014 (Santa launched 2017)
- Model
- B2C / B2B
- Exam systems
- TOEIC · later SAT
- Languages
- Korean · Japanese · English
We record durable facts only — no funding-raised or user-count figures. Unverified fields are marked [TBD] rather than guessed.
Where it sits
Riiid (Santa) is on the EdTech AI 100 map, in exam prep & regional platforms, built in South Korea.