South Korean startup Postmath, operator of the math content creation platform “Math Secretary,” has successfully raised USD 4 million(KRW 5.6 billion) in a Series A round. The investment was joined by the Korea Credit Guarantee Fund, The Invention Lab, Spacetime, and I-Scream Media, bringing Postmath’s total funding to over USD 5.7 million(KRW 8 billion).

Strategic investor I-Scream Media, a leading digital education company for elementary schools in Korea, operates the “I-Scream S” platform, used by over 90% of the nation’s elementary school teachers. Through this partnership, Postmath and I-Scream Media aim to combine Postmath’s advanced math content technology with I-Scream’s extensive school network and platform reach, expecting strong synergy in both domestic and global K–12 education markets.

Postmath’s “Math Secretary” platform is currently used by more than 20,000 instructors and over 100 schools. The platform holds a 90% coverage rate of local math exam data, all of which are made publicly accessible through its proprietary Math Secretary INDEX. Users can freely analyze regional exam trends, school-level textbook adoption, and statistical distributions of question types by year and topic.

Key features include personalized question bank creation, intuitive problem search, automated test sheet generation, and export to editable HWP files. New users gain instant access to 150,000 preloaded questions, which has driven explosive adoption.

Thanks to this usability and high-quality content, Postmath’s revenue grew from USD 0.62 million(KRW 870 million) in 2023 to USD 1.72 million(KRW 2.41 billion) in 2024, and has already surpassed USD 3.21 million(KRW 4.5 billion) in 2025, putting the company on track for annual profitability.

Building on its data-driven foundation, Postmath will launch “Grip Common Math 1 & 2” in November through Math Secretary INDEX. The new hybrid system integrates seamlessly with the Math Secretary platform, enabling real-time DB-linked problem sets, one-click “number variation ×2” worksheets, and instantly usable teaching PPTs.

According to Kyutae Lee, CEO of Kernel House and designer of the upcoming textbooks, “The key differentiator is that Grip is the first textbook designed using the Math Secretary INDEX—moving beyond intuition-driven compilation to data-based structuring. The Grip series will redefine how data shapes educational publishing.”