Enter your staircase measurements to see if a king mattress will navigate the turns — width, landings, and ceiling clearance.
Whether it fits depends on measurements most people get wrong.
Mattress width (76") vs. stair width and landing depth
Item: King mattress: 76" W × 80" L × 10–14" thick
Space: Standard residential staircase: 36" wide, 80" ceiling clearance
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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“Wish I'd used this before trying to force a fridge up the stairs.” — Lesson learned
Measure smart
Four numbers decide nearly every fit check. Get these right and the rest follows.
Don't make these
Most “it didn't fit” stories trace back to one of these oversights.
Frequently asked
Yes — a king mattress is 76" wide vs. 60" for a queen. Those 16 extra inches make landing turns significantly harder because the mattress diagonal is longer. Consider a split king (two twin XLs) if stair clearance is a concern.
01Foam and hybrid mattresses can bend 10–15° safely. Traditional innerspring mattresses should not be folded. For very tight stairs, compress the mattress with ratchet straps around its width to reduce thickness by 2–4 inches.
02A split king consists of two Twin XL mattresses (38" × 80" each). Each half is much easier to carry upstairs. If you're buying new and have a tight staircase, a split king is the best solution.
03Related guides
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