Home & DIY

Crown Molding Calculator

Linear feet, sticks and mitre angles for crown moulding.

Enter your values

Enter the room length in ft.

Enter the room width in ft.

Enter the moulding length sold in ft.

Choose one of: 38 degrees (most common), 45 degrees.

Enter the cost per foot in $.

Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.

Results
Moulding needed
57.2 linear ft
Lengths to buy
5 x 12 ft
Room perimeter
52 ft
Compound mitre angle
31.6 degrees
Bevel angle
33.9 degrees
Material cost
$192.00

Working

  1. 1perimeter 52 ft + 10% waste = 57.2 ft

Quick answer

Add the wall lengths for perimeter, add waste for mitres, then divide by the stick length. Compound mitre angles depend on the spring angle.

perimeter = 2 x (L + W); sticks = perimeter x 1.1 / stick length

At a glance

What it doesLinear feet, sticks and mitre angles for crown moulding.
CategoryHome & DIY
Inputs neededRoom length, Room width, Moulding length sold, Spring angle, Cost per foot
Main outputMoulding needed
Formulaperimeter = 2 x (L + W); sticks = perimeter x 1.1 / stick length
CostFree — no sign-up, no download

How to use the Crown Molding Calculator

  1. 1Measure each wall, or use length and width for a rectangular room.
  2. 2Add 10% for mitres, coping and mistakes on the first few cuts.
  3. 3Set your saw to the compound angles shown, or cut the moulding nested against the fence at 45 degrees.

Inputs explained

Room length(ft)
Enter the room length in ft.
Room width(ft)
Enter the room width in ft.
Moulding length sold(ft)
Enter the moulding length sold in ft.
Spring angle
Choose one of: 38 degrees (most common), 45 degrees.
Cost per foot($)
Enter the cost per foot in $.

Worked example

Using the values the calculator loads with:

Inputs

  • Room length14 ft
  • Room width12 ft
  • Moulding length sold12 ft
  • Spring angle38 degrees (most common)
  • Cost per foot3.20 $

Results

  • Moulding needed57.2 linear ft
  • Lengths to buy5 x 12 ft
  • Room perimeter52 ft
  • Compound mitre angle31.6 degrees
  • Bevel angle33.9 degrees
  • Material cost$192.00
  1. perimeter 52 ft + 10% waste = 57.2 ft

Frequently asked questions

What angles do I cut crown moulding at?

For 38 degree spring crown on a 90 degree corner, use 31.6 degree mitre and 33.9 degree bevel when cutting flat on the saw.

Should I cope inside corners?

Yes. Coped joints stay tight when the house moves; mitred inside corners open up within a season.

What do I need to enter into the Crown Molding Calculator?

Just 5 values: room length, room width, moulding length sold, spring angle, cost per foot. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.

How does the Crown Molding Calculator work out the answer?

Add the wall lengths for perimeter, add waste for mitres, then divide by the stick length. Compound mitre angles depend on the spring angle. It applies the formula perimeter = 2 x (L + W); sticks = perimeter x 1.1 / stick length and shows the working so you can check each step by hand.

Is the Crown Molding Calculator free, and do I need an account?

It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.