# What is a PERT estimate | Lansa

PERT stands for Program Evaluation and Review Technique. It is a software development estimation method. You use it to estimate project duration by determining the weighted average of optimistic, pessimistic, and most likely activity durations. For further details about [***PERT estimates***](https://lansa.com/blog/app-development/software-development-estimation-a-quick-guide/), visit our website.