Header Size Calculator

Find the right header size for any door or window opening — enter the span, wall type, and loading to get a prescriptive header recommendation and cost estimate.

Opening Span (ft)

Building Width (ft)

Pricing (edit to match local rates)

2×6 ($)

2×8 ($)

2×10 ($)

2×12 ($)

LVL ($/LF)

Header Framing

Hover for details • structural cross-section

Recommended Header

2-ply 2×6

For 4 ft opening

Jack Studs (per side)

2 total jack studs

King Studs

1 per side (always)

Assembly Cost

$35.00

Header $15.00 + studs $20.00

Use 2-ply 2×6 for this 4 ft openingBased on IRC R602.7 simplified span tables for SPF #2 lumber, a 2-ply 2×6 is adequate for a 4 ft span in a load-bearing wall with one story above and a 28 ft building width.

This calculator uses simplified IRC R602.7 prescriptive tables for SPF #2 lumber. Actual requirements depend on species, grade, snow/wind loads, and local code amendments. Always verify with your building department or a structural engineer for final sizing.