back-of-the-envelope

idiomPart ofenvelope

back-of-the-envelope — idiom

1. Describing a calculation, estimate, or plan that is done quickly and roughly, wi

1.idiom
Definition

Describing a calculation, estimate, or plan that is done quickly and roughly, without detailed analysis or precise data.

Example

We did a back-of-the-envelope estimate and found the project would cost around fifty thousand dollars.

A back-of-the-envelope calculation suggested the trip would take about three hours by car.