Specificity Calculator

Specificity answers "of all the negative cases, how many did the model correctly say were negative?" It is TN ÷ (TN + FP) — the flip side of recall, which looks at positives. High specificity means few false alarms on the negative class.

Correctly predicted positives.

Predicted positive but actually negative.

Predicted negative but actually positive.

Correctly predicted negatives.

Result

Enter your values and press Calculate — the result appears here.

Worked examples

35 correct out of 45 actual negatives

  • tp = 50
  • fp = 10
  • fn = 5
  • tn = 35

Result: Specificity 0.7778 · False positive rate 0.2222

No false alarms on negatives

  • tp = 30
  • fp = 0
  • fn = 20
  • tn = 50

Result: Specificity 1.00

Frequently asked questions

What does specificity tell me?

Specificity is the true negative rate: of the cases that were actually negative, the fraction the model correctly ruled out. High specificity means the model rarely cries wolf.

How do specificity and recall differ?

Recall looks at the positive class (how many actual positives were found); specificity looks at the negative class (how many actual negatives were correctly identified). A test can be highly sensitive but not specific, or vice versa.

What is the false positive rate?

1 − specificity: the share of actual negatives that were wrongly flagged as positive. It is the x-axis of the ROC curve that ROC-AUC summarizes.

💬 Discuss on BestWordz Community

Join the conversation about Machine Learning, specificity, specificity calculator on the BestWordz Community forum.

Visit Forum →
Copied!