# What is Formula Composer in Plan Tracer?

The program calculates the area of an object using its dimensions on the plan. In practice, there are cases when the dimensions of object on the plan do not coincide with the real ones.

In such cases, creation of the formula for the area and area calculation using real sizes are carried out by means of the Formula Composer dialog. When using the Formula Composer, the object image on the plan doesnâ€™t change.