FilterFit is a directory, not a filter brand

FilterFit helps people match furnace filters by MERV × nominal size × slot depth so a MERV 13 box does not silently choke a 1-inch rack. We do not manufacture filters. We do not invent star ratings.

The site is published by Laqaer Products. FilterFit is live at filterfitguide.com. For corrections, measurement edge cases, or OEM manual quotes we missed, write hello@filterfitguide.com.

Editorial standards

• No fake scores. Brand classes (Filtrete-style, Aerostar-style, Filterbuy-style) describe how products are sold. They are not a 10-point scale.
• MERV is ASHRAE 52.2, not a comfort grade and not a medical claim. House scales such as MPR are labeled as house scales.
• No invented lab numbers. We do not publish a pressure-drop Pascal for a SKU we did not test. We tell you to read the data sheet and the furnace manual.
• Depth before MERV. A 4-inch MERV 13 is not interchangeable with a 1-inch MERV 13.
• Manufacturer airflow guidance wins. If the nameplate or IO manual limits filter type or external static, follow that.
• No other-brand bleed. This property is FilterFit only — not a dumping ground for unrelated Laqaer consumer sites.

How the site is funded

FilterFit is built as a useful bookmark. Some product mentions may later become affiliate links. If that happens, a purchase through those links may earn Laqaer Products a commission. Money does not buy a score here; we do not sell numbered ratings. See privacy for how a content-and-affiliate site handles data.

What we are not

Not an HVAC contractor, not a medical publisher, not a substitute for a static-pressure reading. If the coil ices or the limit switch trips after a filter change, stop experimenting and call a licensed technician.