Furnace filters, scored
These are the furnace filters we rate highest, best score first. What you actually want to compare is how fine a filter traps particles - its true MERV (the one industry standard, ANSI/ASHRAE 52.2). The big sticker numbers, 3M's MPR and Home Depot's FPR, are scales those sellers made up, and they don't map cleanly to MERV - so we show you the real MERV. The "$/yr" figure is what you'll spend on this filter in a year, from its price and how often the maker says to swap it.
If you're wondering why a familiar name scores lower than you expected: when a brand buries its true MERV behind an MPR or FPR number, we cap its honesty score, and a high-MERV filter crammed into a thin 1-inch panel gets flagged because it can choke your airflow. The full reasoning is in the methodology.
FAQ
- How are these furnace filters ranked?
- Best score first. Every score is our opinion under the published furnace-filter rubric, computed from the filter's true MERV (ANSI/ASHRAE 52.2), how plainly that rating is disclosed, airflow fit, and its real annual cost. The full score-event breakdown is on each scorecard.
- What is the difference between MERV, MPR, and FPR?
- MERV (ANSI/ASHRAE 52.2) is the one industry standard for how finely a filter traps particles. MPR is 3M's own scale and FPR is Home Depot's, and neither maps cleanly to MERV - so we always show the true MERV alongside any proprietary number.
- What does the $/yr column mean?
- It is what you will spend on this filter in a year, computed from its real price and how often the maker says to replace it. Prices are sourced and dated, never guessed.
- Why do some familiar furnace filters score lower than expected?
- When a filter is sold under an MPR or FPR number without its true MERV up front, we cap its rating-honesty score. And a high-MERV filter in a thin 1-inch panel gets flagged because it can restrict airflow. The full reasoning is on our methodology page.