Advanced⏱ 7 min read

Software Test Estimation Techniques

Test estimation is the process of predicting the effort, time, and resources required for testing activities. Accurate estimates are a key professional skill — underestimation leads to quality shortcuts; overestimation leads to budget rejection.

◈Key Points

Analogy-based: estimate based on similar past projects — fast but requires historical data.
Three-point estimation (PERT): (Optimistic + 4×Most Likely + Pessimistic) / 6 — accounts for uncertainty.
Function point analysis: estimate based on the number and complexity of functions to be tested.
Work Breakdown Structure (WBS): decompose all test activities to their smallest unit and sum them up.
Always add a risk buffer (typically 15–25%) and make assumptions explicit — estimates made with hidden assumptions become commitments.

⚡ Expert Pro Tip

Track your estimation accuracy on every project. The delta between estimated and actual is your calibration data. Most testers consistently underestimate by 30–40% — know your personal bias.