How do I calculate drywall corner bead quantity?

Add the lengths of all corners requiring bead, then account for joint overlaps and the standard bead stock length.

Does corner bead cover internal corners?

It depends on the selected product; many bead products are used primarily for external corners.

Should I add a cutting allowance?

Yes, where project conditions make offcuts or damage likely.

Drywall trim quantity

Drywall Corner Bead Calculator | Internal & External Corners

Convert corner runs into practical bead quantities. Enter separate external and internal runs when your finishing system treats them differently, then see total length and stock-piece requirements.

Corner bead inputs

External corner count

Average external corner height

Internal taped corner count

Average internal corner height

Bead stock length

Cutting allowance (%)

External bead and internal corner treatment are not interchangeable by default. Use the appropriate product for the actual finish system; this calculator keeps the lengths separate.

Enter corner counts and heights.

Corner-trim requirement

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—External length

—Internal length

—Stock pieces

—Total length

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Corner bead calculation

External length = external corners × average height
Internal length = internal corners × average height
Planning length = total length × (1 + allowance ÷ 100)
Stock pieces = ceiling(planning length ÷ stock length)

Why separate internal and external corners?

Different finishing products and installation methods can apply to internal and external corners. Combining them into one number can hide an important material distinction.

Frequently Asked Questions

Does the tool include internal corners?

Yes, as a separate length.

Can all corners use standard bead?

No. Product suitability depends on the actual corner and finishing system.

Does it include waste?

Yes, through the allowance.

Does it choose bead profile?

No.