MERV, FPR, and Every Filtrete Number Explained: The Full Cross-Reference

Three companies, three numbers, one filter. MERV is the industry standard. FPR is Home Depot’s own scale. MPR is Filtrete’s own scale, printed only on 3M’s Filtrete boxes. None of them measure identically, which is exactly why a “Filtrete 1500” and a “MERV 12” filter can be the same product with two different labels on the shelf. Here’s the full cross-reference, sourced directly from 3M’s own published chart rather than aggregated from blog posts that don’t always agree with each other.

The full MERV / FPR / Filtrete MPR chart {#chart}

MERV	FPR (approx.)	Filtrete MPR	Filtrete product line	Captures
5	—	300	Clean Living Basic Dust	Large particles: dust, lint, some pollen
7	4-5	600	Clean Living Dust Reduction	Household dust, mold spores, pollen
8	5	—	(no Filtrete equivalent; most other brands' "general use" tier)	Common household allergens
11	7	1000-1200	Micro Allergen Defense (1000) / Clean Living Odor Reduction (1200)	Finer dust, pet dander, mold spores; 1200 adds odor capture
12	8-9	1500	Smart Air Filter 1500 (Allergen, Bacteria & Virus)	Allergens, bacteria, virus-carrier particles
13	10	1900-2200	Smart Air Filter 1900 / 2200	Fine particulates, bacteria, most smoke
14	—	2500-2800	Smart Air Filter 2500 / Healthy Living 2800	Ultrafine particles, smoke, most bacteria and viruses

Reading this table: find the number printed on your current filter's box in whichever column matches your brand, then read across to see what it means on the other two scales. If you're comparing filters from different brands while shopping, MERV is the one column that's directly comparable no matter whose box it's printed on.

Why three scales exist at all

MERV comes from ASHRAE, the engineering standards body, and it's the only one built for cross-brand comparison. FPR is a scale Home Depot created to simplify shopping for its own shelf, and it's genuinely coarser than MERV. Manufacturers don't grade Home Depot's house-brand and rebranded filters at every FPR value; in practice you'll mostly see FPR 4, 7, 9, or 10 on the shelf, not a full 1-10 range. MPR is 3M's own scale, specific to Filtrete, measuring capture of the smallest particle range (0.3 to 1 micron) more granularly than MERV alone reports. Full background on what MERV itself measures: MERV Rating Explained.

Do other brands use MERV, FPR, or their own number?

Most of them just print MERV directly. Nordic Pure, Aprilaire, and Honeywell filters sold outside Home Depot label their boxes in MERV, no conversion needed. FPR is specifically a Home Depot-created scale; MPR is specifically a Filtrete-created scale. If your filter box shows a number and you're not sure which system it's from, "MPR" and a number in the hundreds (300-2800) means Filtrete; "FPR" and a single digit (4-10) means Home Depot; anything else printed as a plain number from 1-20 is almost certainly already MERV.

Where this matters: buying the right filter without guessing

Two situations where this chart actually saves you from a bad purchase:

You're restocking the same filtration level from a different brand. Say your system runs a Filtrete 1900 comfortably and you want to try a different brand out of stock concerns or price. Look for MERV 13, not a Filtrete 1900-labeled box from another maker (they don't make one). Which MERV rating fits your situation in the first place: Best MERV Rating for Your Home.

You're chasing wildfire-smoke filtration and want the real ceiling. Filtrete's 2500 and 2800 tiers are both genuinely MERV 14-equivalent per 3M's own chart, a notch above the MERV 13 this site generally recommends as the practical residential ceiling. If your system's blower can handle it (confirm first, see below), a 2800 is the highest filtration Filtrete sells in a standard 1-inch format. Full swap-in, swap-out strategy for smoke season: Best MERV Rating for Your Home.

Before you buy at MERV 13 or higher, on any brand

Every rating on this chart measures filtration, not whether your specific blower can push air through it. MERV 13-14 (Filtrete 1900 and up, FPR 10) is where checking your system's static pressure limit stops being optional. Full explanation of blower type, airflow capacity, and how to check: What Filter Does My Furnace Actually Need?

Where to buy each rating {#where-to-buy}

Real, current listings for the sizes and tiers covered above, checked live rather than guessed:

Size	MERV	Amazon	Home Depot	Lowe's
16x25x1	8	Filtrete 600 MPR	HDX FPR 5	Filtrete 700 MPR
16x25x1	11	Filtrete 1000 MPR	HDX FPR 9	Filtrete 1085 MPR
16x25x1	13	Filtrete 1900 MPR	HDX FPR 12	Filtrete 1900 MPR
20x25x1	13	Filtrete 1900 MPR	HDX FPR 12	Filtrete 1900 MPR
16x25x1	14	Filtrete 2800 MPR	Not stocked at MERV 14 in this size; MERV 13 is HD's ceiling here	Not stocked at MERV 14 in this size; MERV 13 is Lowe's ceiling here
16x25x4 (whole-house)	13	Filterbuy media filter	Honeywell Home media filter	Filtrete 1900 MPR media filter

A pattern worth knowing before you shop: Home Depot doesn't stock Filtrete-branded filters at all in this category, it sells its own HDX house brand (FPR-rated) instead. Lowe's does carry Filtrete direct, including an exact match at MPR 1900/MERV 13. Neither big-box retailer stocks a true MERV 14 filter in a standard 1-inch size; if you want to go past MERV 13, Amazon (Filtrete 2800) is the option among these three. Prices weren't included here since they change constantly, check each link for current pricing.

Frequently Asked Questions

Q: Is a Filtrete 1500 the same as MERV 15?

A: No, and this is the single most common mix-up with Filtrete numbers. A Filtrete 1500 is an MPR number, not a MERV number, and it converts to MERV 12, not MERV 15. The scales use different number ranges (MPR runs into the thousands, MERV tops out at 20) specifically so they're not supposed to look interchangeable, but the coincidence of a Filtrete "1500" and "MERV 15" being close in appearance trips people up regularly.

Q: Which scale should I trust more, FPR or MPR?

A: Neither is more "correct" than the other since they measure different things and aren't ASHRAE-standardized, but MPR has a precise, publicly documented conversion from the manufacturer (used for this chart); FPR does not, and Home Depot's own scale is coarser to begin with. If precision matters to your decision, use the MERV column as your reference point.

Q: My filter box just says a MERV number already. Do I need this chart?

A: No; if your box already prints MERV, that is the standardized number, and this chart exists specifically to translate FPR or MPR-only boxes back into it.

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Related: HVAC Air Filters: Sizes, MERV Ratings, and How Often to Replace Them · MERV Rating Explained · Best MERV Rating for Your Home · MERV 8 vs. 11 vs. 13 Compared · What Filter Does My Furnace Actually Need?