# Fermi Problem

Category

Also Known As...

B a c k - o f - t h e - E n v e l o p e C a l c u l a t i o n , B a l l p a r k , G u e s s t i m a t i o nSimilar

rec2n6ezMtdpvML9o recaSgITSy3DMaCY1## Definition

A rough calculation to arrive at a reasonable estimate — unknowns and all — where the result could be considered logically approximate.## Origin

Named for physicist Enrico Fermi's ability to make good approximate calculations with little or no actual data.