Last updated: March 2026
Enter your doorway measurements to see if a king mattress will clear the frame — and what to do if it won't.
Whether it fits depends on measurements most people get wrong.
Mattress thickness (10–14") vs. door clear width (30–32")
Item: King mattress: 76" W × 80" L × 10–14" thick
Space: Standard interior door: 80" H × 30–32" W clear opening
Actual clear openings are usually 1–2″ smaller than the labeled size.
Your exact dimensions probably aren't "standard." Small measurement errors cause big problems — 1 inch can be the difference between fitting and getting stuck.
Verdicts are calculated by comparing all 6 item orientations against the space dimensions using verified building code standards. See our methodology
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1 inch can be the difference between fitting and getting stuck.
“Checked my mattress before ordering. Tight fit, but it worked with the door removed.” — Online shopper
Measurements verified by the ItemFits engineering team · Based on IRC R311.2, IBC Chapter 10, ADA 404 · Our methodology
Standard sizes say it works — but your measurements are what matter.
Yes, if you stand it on its side. A king mattress on its side is 76" tall × 80" long × 10–14" thick. The 10–14" thickness easily clears a 30" door. The 76" height clears the 80" header. See the detailed 30-inch door analysis.
Foam mattresses can be compressed by 2–3 inches with ratchet straps. For rigid innerspring models, remove the door (adds 1.5–2") and remove door casing trim if needed (adds another 0.75–1.5").
A door is almost always easier. Stand the mattress on its side and slide it through. Windows require lifting height, removal of screens/sashes, and risk of damage. Only use a window if the doorway path has an impassable turn.