To balance the chemical equation between KOH and H3PO4, we need to make sure that the number of atoms of each element is the same on both sides of the equation. Here's the balanced equation:

3KOH + H3PO4 → K3PO4 + 3H2O

In this equation, we have:

- 3 atoms of potassium (K) on both sides

- 1 atom of phosphorus (P) on both sides

- 4 atoms of oxygen (O) on both sides

- 3 atoms of hydrogen (H) on both sides

Therefore, the equation is balanced.