Zach Korzyk created DeltaMath in 2009 when he wrote a simple program on substituting values into the Quadratic Formula. Positive student response prompted him to kick into gear and create content for the rest of the school year.

In its first full year as a functional site, DeltaMath was used by 100 teachers and 5,000 students. In the years to come, Zach worked nights, weekends, and summers adding content and features. He taught himself database management, web servers, and JavaScript. By 2019-2020, the site had grown to over 100,000 teacher-users and 4 million students.