The word "mis-calculated" refers to an incorrect calculation or estimation. Antonyms for "mis-calculated" would include accurately calculated, correctly estimated, precisely calculated, or correctly computed. These words indicate that the calculation or estimation was done correctly and without error. Other antonyms for "mis-calculated" might include well-planned, well-considered, or well-prepared, implying that the calculation or estimation was well thought-out and executed successfully. No matter which antonym is used, the implication is that the calculations or estimations were done with precision and care, resulting in an accurate and successful outcome.