16x25x5 Furnace Filter Exact Actual Dimensions & Cross-Reference Chart
A '16x25x5' furnace filter is almost never 16" x 25" x 5". Actual caliper thickness ranges from 4.38" (4-3/8") on Honeywell & Lennox cabinets up to 5.25" (5-1/4") on Goodman/Amana media cabinets. Ordering the wrong brand jams the cabinet door or leaves a 7/8" bypass gap.
⚠ CRITICAL FIT RULE: Measure your old filter's depth with a tape measure before buying. If your cabinet takes 4-3/8" depth (Honeywell FC100A1029 / Lennox X6670), a 5-1/4" Goodman filter WILL NOT slide in.
Verified Reddit Fit Complaint:
r/HomeImprovement — 'My replacement 16x25x5 air filter is too big for my slot'
Verified X Fit Complaint:
@MyRoostOfficial — 'Why do 5-inch furnace filters marked 16x25x5 vary by 3/4 inch in thickness?'