Find your exact air filter size — and never reorder again.

Filter sizes are written as Length × Width × Depth in inches — for example, 20x25x1. The number is almost always printed on the cardboard frame of your existing filter. If it isn’t, measure all three sides and round each up to the nearest inch.

The nominal size is the rounded number printed on the frame (like 20x25x1). The actual size is slightly smaller — usually about ½ inch less on length and width — so the filter slides in and seats properly. Always order by the nominal (printed) size.

No. A 16x25x1 and a 25x16x1 are the same filter. Our finder matches your size whichever way you enter the two face dimensions. Only the depth (the third number) has to be exact.

MERV 8 is everyday protection for dust, lint, and pollen — the right choice for most homes and rentals. MERV 10 steps up to finer particles. MERV 13 captures the smallest particles and is best where indoor air quality matters most. Higher MERV is more effective but check that your system’s airflow can handle it.

Pick how often you want filters delivered, and we ship the right size automatically — 15% below the one-time price, every delivery. You can change the schedule, skip a shipment, or cancel anytime. No contracts.

Unusual sizes are usually custom-cut filters, and we make those too. Request your size and we’ll quote it and set up delivery. For properties juggling many odd sizes, our free site audit maps every one so you never have to guess again.