Will It Fit Calculator
| Opening | Flat pass | Tilted pass | Trick that helps |
|---|---|---|---|
| 30-in door | depth < 30 | diagonal < 30 | remove door + trim: +2-3 in |
| 32-in door | depth < 32 | diagonal < 32 | remove legs first |
| 36-in door | depth < 36 | diagonal < 36 | usually fine on edge |
The question is never the doorway alone: a doorway is 30 to 36 inches wide, but the couch travels on its edge through the smallest rectangle of the route - the door, then the hallway width, then the corner where the hallway turns, and the diagonal of the furniture's depth is what actually has to pass through each.
Bottom line: a 38-inch-deep couch tilts on its side into a 38-inch diagonal, which passes a 36-inch door only if the couch is thinner than 12 inches or the frame comes off - and the hallway corner is where the honest arithmetic lives, because a 90-degree turn needs a clearance pocket twice the furniture's depth.
The honest part: the sofa-moving problem is real mathematics - some couches mathematically cannot make some corners - and the calculator's answer is sometimes 'disassemble the legs, remove the door, or sell it in the hallway.' Measuring twice costs five minutes; returning a couch costs the delivery fee and the argument.
How to use
- Measure the furniture at its three extremes: height, width and depth - including the legs, arms and any bulge that sticks past the frame.
- Measure every opening on the route: doors at the narrowest (frame inside), hallways at the tightest point, and the corner depth where two hallways meet.
- Read the verdict, then run the tricks in order - tilt on edge for the diagonal, remove doors and legs, rotate mid-door - before declaring the couch immovable.
Frequently asked questions
How do I know if my couch will fit through the door?
The couch must pass through each opening on its smallest face, so compare the couch's depth (on edge) against the door's width: a 36-inch door passes any couch shallower than 36 inches on edge. If the depth is bigger, the diagonal helps - tilting a 38-deep by 30-tall couch gives a 48-inch diagonal that fits the 36-inch door if the couch is under about 34 inches tall.
What is the moving sofa problem?
It is the mathematician's version of your Saturday: what is the largest-area shape that can move around a right-angled corner in a unit-width hallway? The answer, proven in 2024 after nearly sixty years, is a bizarre shape with an area of about 2.2195 - which is the gentle way of saying some couches genuinely cannot make some corners, no matter the wiggling.
How much clearance does a hallway corner need?
A 90-degree turn needs a corridor width that depends on the furniture's length and depth together: a 90-inch-long, 35-inch-deep sofa wants a hallway at least 43 inches wide to turn, and tighter corners need the vertical trick - standing the couch on its arm and rotating like a propeller. Measure the corner pocket, not just the hallways.
Should I remove the door to get furniture through?
Yes, when the math is close: pulling the door and its hinge pins adds two inches of width, taking the trim off adds another, and the doorstop molding is the part that actually measures 30 inches. A screwdriver, five minutes and a helper hold the door - the cheapest renovation the move will ever include.