🔨 Stud Wall Framing Calculator

Calculate studs, plates, and framing materials

Wall Dimensions

Total wall length
Floor to ceiling
On-center spacing
Standard 3' doors
Standard 3' windows
💡 From Rob Chen, 16 years framing:

"Here's what nobody tells beginners: buy 10% extra studs. Lumber isn't perfect—you'll reject twisted ones, cut one too short, split an end nailing. I've framed hundreds of walls and I still mess up cuts. Also, studs come in 92-5/8" (precut for 8' walls) or 96" or 104-5/8" lengths. Don't assume 'stud' means 8 feet. Measure your actual wall height minus the three plates (4.5" total) to know what length to buy. And always check EVERY stud for straightness before nailing—a crowned stud will haunt you forever when you're hanging drywall."

📐 Understanding Wall Framing

A stick-framed wall consists of vertical studs sandwiched between horizontal plates. The math is simple once you understand on-center (OC) spacing.

Basic Components

  • Bottom Plate (Sole Plate): Sits on subfloor, studs nail to it
  • Top Plate: Connects to top of studs
  • Double Top Plate (Cap Plate): Second layer on top, ties walls together
  • Studs: Vertical 2x4s or 2x6s spaced 16" or 24" OC
  • King Studs: Full-height studs flanking door/window openings
  • Jack Studs (Trimmers): Shorter studs supporting headers
  • Headers: Horizontal beams over openings, sized for span/load
  • Cripples: Short studs above/below openings

Common Mistakes

1. Wrong Stud Count: Formula is (Wall Length ÷ Spacing) + 1, PLUS 2 end studs. A 12' wall at 16" OC needs (144 ÷ 16) + 1 + 2 = 12 studs, not 9.

2. Forgetting Extra Plates: You need THREE plates per wall (1 bottom + 2 top), not two. Each plate equals wall length.

3. Using Wrong Stud Length: For 8' ceiling, buy precut 92-5/8" studs (leaves room for 3 plates + drywall). Don't buy 96" studs and cut them—waste of time.

4. Inadequate Headers: A 3' door opening needs a 4x4 or doubled 2x6 header minimum. Check code—undersized headers fail inspection.

❓ FAQ

What does 16 OC mean?

16 inches on-center—distance from center of one stud to center of next. Creates 14.5" actual gap (since 2x4 is 1.5" wide).

How many studs for a wall?

Formula: (Length in inches ÷ Spacing) + 1 + 2 ends. Example: 12' wall at 16" OC = (144 ÷ 16) + 1 + 2 = 12 studs.

2x4 or 2x6 studs?

2x4 for interior walls and most exterior walls. 2x6 for exterior walls needing R-19+ insulation or walls over 10' tall.