What is the rough opening for a 32 inch door?

34" wide by 82" tall, for a 32" × 80" slab in a 3/4" jamb with 1/4" of shim space, a 1/2" gap under the door and 1/2" of flooring still to go down. That is the framer's shorthand — slab plus 2" wide, plus 2" to 2 1/2" tall — added up from the parts, which is why a thicker exterior jamb or a thicker floor moves it. A prehung door's own instructions beat both.

Does the rough opening height include the flooring?

Yes. A door's rough opening is measured from the subfloor, so any floor still to come is inside it. With the finished floor already down the 32" × 80" door above wants 81 1/2"; with 3/4" of hardwood still to go down it wants 82 1/4". Frame for the floor you will have, not the one you are standing on, or the door gets planed to fit later.

How much bigger than the window should the rough opening be?

Whatever the window maker says — every brand prints a rough opening for each unit, and it is usually about 1/2" over the frame in each direction, which is the calculator's default. A 35 1/2" × 47 1/2" unit then wants 36" × 48". Check the sheet before framing: some makers ask for 3/4", and a window that will not go in is a re-frame.

How long are the jack studs for a door?

From the top of the bottom plate to the underside of the header — the rough opening height less the plate. For the 32" door above that is 82" less 1 1/2", so 80 1/2". The plate between the jacks is cut out once the wall is standing.

What size header does a door opening need?

This site will not say, on purpose. A header's depth depends on its span, the species and grade, the snow load and what bears on that wall, and a wrong guess is a structural mistake. Take it from your code's header span tables, an engineer or the building department, then put that depth into the calculator: it works out the header's length, the jack studs and the cripples that follow from it, and tells you if it fits under the top plates.

Door and window rough opening calculator

Enter the door slab or the window unit. This adds up the jambs, shims and floor to the rough opening, then places the king and jack studs and the header you choose around it.

Opening for

Slab width

Slab height

Header depth

= 9.25"

Jack studs per side

From your span table

Advanced settings3/4" jamb · 1/4" shims · 1/2" floor · 1/2" under · 92 5/8" studs · 24" from the end

Jamb thickness

= 0.75"

Shim gap

= 0.25"

Finished floor

= 0.5"

Gap under the door

= 0.5"

Stud thickness

= 1.5"

Bottom plate

= 1.5"

Stud length

= 92.625"

Stud spacing

Opening's left edge

From the wall end, or whatever mark you lay out from

Frame the rough opening

Width

34"

Height

82"

From the subfloor

Where the size comes from

Width32" slab + 2 × (3/4" jamb + 1/4" shim): 34"
Height80" slab + 3/4" head jamb + 1/4" shim + 1/2" under the door + 1/2" of floor: 82"
The framer's shorthandSlab plus 2" wide and 2–2 1/2" tall — a cross-check, not a spec: 34" × 82"–82 1/2"

Framing pieces

King studsFull height, one each side: 2 × 92 5/8"
Jack studsBottom plate to the underside of the header: 2 × 80 1/2"
HeaderOver the opening and a jack each end, 9 1/4" deep: 37"
Cripples aboveHeader to the top plates, on the wall's layout: 2 × 2 7/8"

Plate layout

Each piece's left and right face, measured from the same reference — mark the plates together and every one lines up.

King stud: 21" – 22 1/2"
Jack stud: 22 1/2" – 24"
Rough opening: 24" – 58"
Jack stud: 58" – 59 1/2"
King stud: 59 1/2" – 61"

Before you cut

All 2 checks passShow the numbers

The header fits under the top plates — passes2 7/8" left above the header for cripples.
Room for the king and jack studs on the left — passesThe king stud's outside face lands 21" from the reference.

This does not size the header

The header depth and the jack stud count are asked for because they are structural: what a header has to be for its span depends on species, grade, snow load and what bears on that wall. Take them from your code's span tables, an engineer, or the building department — and ring them before you frame a bearing wall. This page does the geometry that follows from the decision. And the door's own installation sheet beats any rule here: where it gives a rough opening, frame to that.

Worked example: a 32" × 80" door

A 32" × 80" slab in a 3/4" jamb with 1/4" of shim space, a 1/2" gap under the door and 1/2" of flooring still to go down needs a 34" × 82" rough opening — inside the framer's shorthand of 34" by 82" to 82 1/2".

With one jack a side and a 9 1/4" header (a depth you choose; this does not size it), the jacks are 80 1/2", the header is 37" long and the cripples above it are 2 7/8".

It passes all 2 of the framing checks the calculator applies.

Rough opening: 34" × 82"
King studs: 2 × 92 5/8"
Jack studs: 2 × 80 1/2"
Header length: 37"
Cripples above: 2 × 2 7/8"

These are the figures the calculator above opens on. Change any field and it works the same problem for your numbers.

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About rough openings

What is the rough opening for a 32 inch door?: 34" wide by 82" tall, for a 32" × 80" slab in a 3/4" jamb with 1/4" of shim space, a 1/2" gap under the door and 1/2" of flooring still to go down. That is the framer's shorthand — slab plus 2" wide, plus 2" to 2 1/2" tall — added up from the parts, which is why a thicker exterior jamb or a thicker floor moves it. A prehung door's own instructions beat both.
Does the rough opening height include the flooring?: Yes. A door's rough opening is measured from the subfloor, so any floor still to come is inside it. With the finished floor already down the 32" × 80" door above wants 81 1/2"; with 3/4" of hardwood still to go down it wants 82 1/4". Frame for the floor you will have, not the one you are standing on, or the door gets planed to fit later.
How much bigger than the window should the rough opening be?: Whatever the window maker says — every brand prints a rough opening for each unit, and it is usually about 1/2" over the frame in each direction, which is the calculator's default. A 35 1/2" × 47 1/2" unit then wants 36" × 48". Check the sheet before framing: some makers ask for 3/4", and a window that will not go in is a re-frame.
How long are the jack studs for a door?: From the top of the bottom plate to the underside of the header — the rough opening height less the plate. For the 32" door above that is 82" less 1 1/2", so 80 1/2". The plate between the jacks is cut out once the wall is standing.
What size header does a door opening need?: This site will not say, on purpose. A header's depth depends on its span, the species and grade, the snow load and what bears on that wall, and a wrong guess is a structural mistake. Take it from your code's header span tables, an engineer or the building department, then put that depth into the calculator: it works out the header's length, the jack studs and the cripples that follow from it, and tells you if it fits under the top plates.