Which MERV rating do I need?

MERV is a number from 1 to 16 that tells you how much an air filter catches. Higher numbers catch smaller particles. For most homes, the choice comes down to three.

MERV 8: Everyday

Catches dust, lint, pollen and other larger particles. It's the right pick for most homes without pets or allergies, and it's gentle on airflow.

MERV 11: Allergy

Adds pet dander and mold spores. Pick this if you have pets or anyone at home has allergies.

MERV 13: Allergy + Smoke

Also catches much finer particles, including smoke and smog. The EPA suggests MERV 13 or higher when wildfire smoke is a concern, as long as your system can handle it. It's also a good choice if someone at home has asthma.

Can my system handle MERV 13?

Most modern home systems can. Finer filters let a little less air through, so if yours is older, runs noisy or struggles to keep up, check with your HVAC technician. Thicker 4" and 5" filters have more surface area and ease the load at any MERV.

How the ratings are measured

MERV comes from a standard lab test (ASHRAE 52.2) that measures how much of each particle size a filter catches. We'll publish the lab report for each Caliper grade as soon as testing is done.

Shop by grade

Every Caliper size comes in all three grades, at the same fit.