Door Header Size Chart: Span, Load & Lumber Sizes 2026

How door header size is worked out

A header is sized by the opening it spans. The rule of thumb for a single-story load-bearing wall, with doubled 2× lumber, is: an opening up to 36 in takes a 2×6, up to 48 in takes a 2×8, up to 72 in takes a 2×10, and up to 96 in takes a 2×12. The actual depths are 5.5 in for a 2×6, 7.25 in for a 2×8, 9.25 in for a 2×10 and 11.25 in for a 2×12, because a 2×6 is not 6 inches deep once it is milled. The jack studs carry the header: 1 per side up to 72 in, and 2 per side over 72 in, because a wide header bears more load. The king studs run full height on each side: 1 per side at every width.

At the default — 36 in — the header is a 2×6, which is 5.50 in deep, or 5.5 × 2.54 = 13.97 cm, with 1 jack and 1 king stud per side. A 48 in opening takes a 2×8, which is 7.25 in deep, or 18.42 cm, also with 1 jack and 1 king per side. An 84 in opening takes a 2×12, which is 11.25 in deep, or 28.58 cm, with 2 jack studs and 1 king per side.

This is a size chart, and it is explicitly a rule of thumb, not a structural-engineering verdict: it does not say what a two-story load, a roof truss load or a point load above the opening needs, and it does not replace the span tables in your local building code. Check local code and consult an engineer for load-bearing walls, for any opening over 96 in, and for any wall carrying more than one story.

The worked example, line by line

Setup: 36 in opening.

Line 1 — the header. 36 in is 36 in or under, so the header is a 2×6.

Line 2 — the depth. A 2×6 is 5.50 in deep in fact, not 6 in.

Line 3 — the depth in centimetres. 5.5 × 2.54 = 13.97 cm.

Line 4 — the jack studs. The opening is 72 in or under, so it needs 1 jack stud per side.

Line 5 — the king studs. Every opening needs 1 king stud per side.

Every branch, checked

24 in opening: the header is a 2×6, 5.50 in deep (13.97 cm), with 1 jack and 1 king per side. A narrow opening takes the smallest header, and the 2×6 is the same from 24 in to 36 in.

48 in opening: the header is a 2×8, 7.25 in deep (18.42 cm), with 1 jack and 1 king per side. At 48 in the 2×6 is no longer enough, so the header steps up to a 2×8.

60 in opening: the header is a 2×10, 9.25 in deep (23.50 cm), with 1 jack and 1 king per side. A 60 in opening is a wide doorway or a small patio door, and it needs the deeper 2×10.

84 in opening: the header is a 2×12, 11.25 in deep (28.58 cm), with 2 jack studs and 1 king per side. Over 72 in the header bears enough load to need a second jack stud on each side.

96 in opening: the header is a 2×12, 11.25 in deep (28.58 cm), with 2 jack studs and 1 king per side. This is the widest opening in the chart: 96 in is an 8-foot opening, and it is the limit of doubled 2×12 lumber by this rule of thumb.

120 in opening: the answer is an engineered LVL sized by an engineer, not a 2×12. Over 96 in, doubled dimensional lumber is no longer the answer by this rule of thumb: the header is an LVL or a steel beam, and its size comes from an engineer or the LVL maker’s span tables.

30 in opening: the header is a 2×6, 5.50 in deep (13.97 cm), with 1 jack and 1 king per side. A 30 in door is a standard closet or bathroom door, and it takes the same header as a 36 in door.

42 in opening: the header is a 2×8, 7.25 in deep (18.42 cm). At 42 in the opening is past the 36 in limit of the 2×6, so it steps up to a 2×8 even though it is only 6 in wider.

Reverse — header to opening: a 2×6 header spans up to a 36 in opening, a 2×8 spans up to 48 in, a 2×10 spans up to 72 in, and a 2×12 spans up to 96 in. Measure the header you have, and the opening follows, because the header size sets the widest opening it can carry by this rule of thumb.

What the defaults assume

The model assumes a single-story load-bearing wall with doubled 2× lumber, a normal roof load above, and a header bearing on jack studs with king studs full height on each side. It assumes the opening is measured between the king studs, and it assumes the lumber is standard dimensional stock, so a 2×6 is 5.5 in deep in fact. It leaves out two-story loads, truss loads, point loads, snow loads and seismic loads, which can all demand a deeper header, and it does not cover non-load-bearing walls, where the header is only holding up the drywall above the door. Rounding convention: sizes to 2 decimals, centimetres to 2 decimals, and all figures are computed from unrounded values, rounded only for display.

Output · formula · meaning

Who uses this

• The homeowner framing a new interior door: they learn a 36 in opening takes a 2x6 header, 5.50 in deep — so they know the exact lumber to buy, and they check the 1 jack and 1 king stud per side before they cut.
• The DIYer widening a doorway to 60 in: they learn a 60 in opening takes a 2x10 header, 9.25 in deep — so they know the 2x6 they have is not enough, and they check the 23.50 cm depth against the wall before they frame.
• The remodeler opening an 8-foot wall: they learn a 96 in opening takes a 2x12 header with 2 jack studs per side — so they know the header needs a second jack on each side, and they check the 11.25 in depth against the ceiling height.
• The homeowner with a header already in place: they learn a 2x10 header spans up to a 72.00 in opening — so they know the header they have will carry a 60 in door, and they check the 2x12 at 96 in before they widen further.

Accuracy & limitations

The math is exact for the numbers you enter: the header follows the opening width by the chart, the depth is the actual lumber depth, the centimetres are the inches times 2.54, and the jack studs are 1 per side up to 72 in and 2 per side above it. What the model cannot do is read your wall for you: check whether the wall is load-bearing, what load sits above it, and what your local code’s span tables say, because a two-story load or a truss load can demand a deeper header than this chart gives. It assumes a single-story load-bearing wall with doubled 2× lumber and a normal roof load, and it leaves out snow loads, point loads and seismic loads. It is explicitly a rule of thumb, not a structural-engineering verdict: consult an engineer for load-bearing walls and for any opening over 96 in. For the studs, see stud size chart; for the joists below, see deck joist span chart.