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Duct Sizing Calculator

Calculate duct cross-sectional area and equivalent round diameter from required CFM and target air velocity per ACCA Manual D.

Duct Sizing Calculator

Calculate duct dimensions from required CFM and target air velocity.

Round Duct Diameter10inches
Required Cross-Section Area64.0sq in
Source: ACCA Manual D. Formula: Area = CFM / velocity. Round duct diameter rounded up to nearest inch for standard sizes.

For reference only. Verify with your local building code and a licensed professional before making decisions.

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