In this talk we revisit the holographic calculation of 1/2-BPS four-point functions from IIB supergravity compactified on AdS_3\times S^3\times K3. I will present evidence that the four-point functions exhibit a hidden 6d conformal symmetry. Using this hidden symmetry, we conjecture a general formula for all 1/2-BPS four-point functions of different conformal dimensions. We also develop a bootstrap-like algorithm to directly compute the correlators and check this proposal. Our method simplifies the traditional approach by exploiting the superconformal symmetry and eschews the knowledge of the (unknown) supergravity effective quartic vertices. We find the supergravity calculations are in perfect agreement with our conjecture.