Interactive fit calculator
Comforter size and drop calculator
Retail size names vary. Calculate a target width and length from the mattress beneath your bedding, then compare those numbers with the listing.
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How this tool works
Width equals mattress width plus twice the chosen side drop. Length equals mattress length plus the chosen extra coverage at the foot. Mattress presets use common US nominal dimensions; always measure your actual mattress and permanent topper before purchase.
Results are decision support, not lab measurements or medical advice. Verify current dimensions, materials, care instructions and availability with the manufacturer before buying.