Correlation Coefficient Calculator (Matthews)

Find the Matthews correlation coefficient (MCC) for a classifier.

MCC 0.6508

Formula: MCC = (TP·TN − FP·FN) ÷ √((TP+FP)(TP+FN)(TN+FP)(TN+FN))

Step-by-step with your numbers:

1. Values used:

2. True positives = 80

3. True negatives = 85

4. False positives = 15

5. False negatives = 20

7. MCC = 0.6508

Did we solve your problem today?

MCC is a balanced measure of binary classification quality, even on imbalanced data.

The math behind it

MCC ranges from −1 (total disagreement) through 0 (random) to +1 (perfect).

TP 80, TN 85, FP 15, FN 20 → MCC ≈ 0.65.

Why prefer MCC over accuracy?

It stays informative when classes are imbalanced.