Every California smog check term and question, plainly defined

What is the difference between smog and emissions?

Smog check is California's emissions inspection program.

Per BAR (bar.ca.gov/smog-check).

This entry also has a full Q&A treatment: smoganswers.com/q/what-is-the-difference-between-smog-and-emissions/

View in the A–Z glossary →

Last reviewed 2026-05-25 · Cal Smog Network canonical answer library