About Us

SumFrog builds fast, free online calculators and original data resources. Every tool shows its exact formula, a worked example, and the official sources behind any rates or reference values it uses.

We built SumFrog because too many calculator sites hide their math. Our rule: if we can't cite it, we don't publish it.

[EDIT] 운영자 소개 1~2문장 추가 — E-E-A-T를 위해 실명/경력 공개 권장.