The Honeywell FC100A1029 whole-house filter is labeled “16x25x4” but actually measures 15.875 x 24.75 x 4.25 inches. Unlike 1″ filters, 4″/5″/6″ whole-house filters don't share one universal nominal-to-actual conversion — always match by brand and model, not just the printed size.
For F100F/F150E media cleaners. Resellers vary by up to ⅛" on depth. No manufacturer spec sheet found for this exact figure — based on consistent independent reseller measurements.
Match by brand + model, not nominal size. Confirm against your old filter or equipment manual before ordering.
Looking for a 1″ furnace filter instead? Use the full FilterKey tool.