Calculapedia

Crown Molding Calculator

How much crown molding do you need? Enter your room size.

Ceiling perimeter
With 12% waste
Estimated cost
Shop crown molding →

How this calculator works

Crown molding runs the full perimeter of the ceiling. The calculator adds up all four walls and adds 12% for the angled miter cuts at every corner, which waste more than straight trim.

Worked example — a 14 ft × 12 ft room:
Perimeter 52 ft × 1.12 = 59 linear feet.

Corners eat material

Inside and outside corners on crown are cut at compound angles, so mistakes are common. The 12% cushion gives you room to redo a bad cut.

Frequently asked questions

How do I measure for crown molding?

Add up the length of all the walls in the room (the ceiling perimeter), then add about 12% for waste.

Why does crown waste more than baseboard?

The compound miter cuts at corners are harder to get right, so extra material saves a second trip.

Planning a wall or paint project

Surface condition matters as much as area. Rough, porous, repaired, or strongly colored surfaces may need extra primer or paint. Check the coverage printed on the product you plan to use and account for trim, ceilings, openings, and a second coat where applicable.

How to use this estimate

Accuracy and limitations

Calculapedia provides educational planning estimates. It does not inspect your site, select products, guarantee quantities, or replace a contractor, engineer, architect, building official, or supplier. Confirm the final quantity and any safety or code requirements before buying or building.

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