14x18x1 MERV 8 Furnace & AC Air Filter
The 14x18x1 (actual size 13.5 × 17.5 × 0.75 in) in MERV 8 — captures pollen, dust, lint, dust-mite debris and mold spores. Best for everyday home use — the standard choice to protect your HVAC system. Below: the true dimensions, when to change it, and how this MERV compares to the others that fit the same slot.
Same size, other MERV ratings
All fit your 14x18x1x1 slot — step up for finer filtration, down for easier airflow.
Measured your slot? Other depths
Depth must match your filter slot exactly. Same 14x18x1 face, different thickness.
Frequently asked questions
What is the actual size of a 14x18x1 air filter?
A 14x18x1 is the nominal size printed on the frame. The true measured size is about 13.5 × 17.5 × 0.75 in, cut slightly under so the filter slides into the 14x18 slot. This is standard across all brands.
What does MERV 8 filter out?
MERV 8 captures pollen, dust, lint, dust-mite debris and mold spores. It's best for everyday home use — the standard choice to protect your HVAC system. On the box you may see it labelled MPR ~600 (3M/Filtrete) or FPR 5 (Home Depot).
How often should I change a 14x18x1x1 filter?
Change it every 60–90 days. A 1" filter clogs quickest, so check it monthly. A clogged filter strains your blower and raises energy bills.
Will a 14x18x1x1 filter fit my furnace?
Air filters are universal by size — any furnace, AC or return grille that takes a 14x18x1x1 filter will fit this one, regardless of the HVAC brand. Just match the three numbers on your old filter's frame exactly, depth included.