by Amit Shekhar · 1 August 2026
Precision vs Recall
Precision vs Recall, the two numbers we use to measure how good a system is at making yes-or-no decisions. We will also see how Precision and Recall differ from each other and when to use which one, what the four possible outcomes of any such decision are, why these two numbers pull against each other, and how the cost of a mistake decides which one we must care about more.
Read on Outcome School ↗then come back to lock it in
Before you read, guessWhat question does precision answer regarding the flagged items?
Ten seconds, a guess, then read — a wrong guess still makes the answer stick.
What this article covers
- The problem we are trying to solve
- The four possible outcomes
- What is Precision?
- What is Recall?
- Precision vs Recall
- When to use which one?
- A quick recap of the formulas
- Summary
The article lives on outcomeschool.com. Read it there, then come back: the tutor in the margin has read it and will answer questions, and the questions below check what stayed.