Top 10 Best Duct Calculator Software of 2026

McQuay Duct Sizer focuses on producing duct dimensions from airflow targets using friction-loss calculations and duct configuration inputs. The workflow fits design and estimating teams that need fast, repeatable dimension outputs without switching between multiple calculation spreadsheets. The interface supports iterative parameter changes so users can converge on a duct size that stays within velocity and layout constraints. It also generates results in a form that can be carried into downstream design documentation.

A key tradeoff is that it is less suited to advanced research-grade modeling because it does not replace CFD or flow network tools for complex geometries. A practical usage situation is pre-design sizing during schematic and estimate phases, where consistent friction-loss assumptions matter more than high-fidelity turbulence prediction. It is also a fit when the primary goal is to document duct sizes quickly for standard rectangular runs rather than build a full duct system model.

Carmel Software Duct Calculator is suited to duct sizing tasks where the output needs to map cleanly into a duct construction workflow, including fitting loss coefficients and pressure budgeting inputs. The calculator approach supports iteration by keeping the friction loss logic and fitting treatment consistent across reruns. This design reduces the risk of mixing incompatible assumptions when updating duct routes or airflows late in a layout cycle.

A key tradeoff is that the tool is best at duct calculation rather than full CAD layout or full-system coordination, so it does not replace Revit MEP design authoring for duct routing. Carmel Software Duct Calculator works well for sizing smaller scopes like a single air-handling unit branch, a riser segment, or a departmental ventilation zone where calculations and pressure summaries must be consistent.

Autodesk Revit covers duct layout, system assignment, and documentation using its BIM data model, so duct sizes and fittings become part of the same authoring environment. Revit MEP interoperability supports exchanging model data with other BIM tools, and schedules can be used to generate duct quantity and size reporting from the model. The automation surface includes a documented API for adding rules, validation, and custom calculation workflows around duct elements.

A tradeoff is that Revit is not a dedicated equal-friction-method calculator and often requires modeling discipline to make sizing outputs consistent across disciplines. Revit fits best when duct sizing must stay synchronized with routing intent, penetrations, and drawing production, not when a team only needs a fast standalone duct sizing result.

Ductsize is a duct calculator software aimed at producing duct dimensions from airflow and pressure-loss inputs. It focuses on friction-loss based sizing with common HVAC duct configurations and a fitting loss approach driven by coefficient libraries.

The workflow supports iterative updates so users can converge on acceptable static pressure and air velocity limits. Ductsize is best evaluated on how consistently it handles equivalent length and pressure-class style constraints across rectangular duct runs.

ASHRAE Duct Fitting Database provides published duct fitting data and loss guidance intended for duct pressure and friction loss calculations. The database focuses on fitting loss coefficients and equivalent length methods needed to translate fittings into duct pressure budget terms.

Its value is tied to using ASHRAE-referenced fitting libraries as a source of coefficients for friction loss workflows. It supports straightforward manual incorporation into duct sizing calculations rather than running end-to-end duct sizing automation inside a calculator UI.

Design Master HVAC is a duct calculator geared toward HVAC design work that needs repeatable sizing results and practical workflow for duct and fittings. The tool supports duct sizing calculations using standard loss approaches, then helps translate results into pressure-oriented decision making for layout and system planning.

It also provides a ductwork-specific fittings library so equivalent length and fitting loss accounting can stay consistent across projects. Automation is mainly worksheet-driven through templates and saved calculation setups rather than code-based extensibility.

Wrightsoft Right Suite positions duct sizing and design around calculation workflows that can attach to real project documentation outputs. The toolset supports rectangular duct sizing with friction loss calculations and pressure-based selection needed for HVAC duct design deliverables.

It also integrates ductwork layout outputs through CAD-oriented exchanges that help reduce re-entry of sizes. Automation is centered on repeatable sizing runs and standards-driven defaults rather than one-off calculators.

Cool Calc is a duct calculator tool built for repeatable duct sizing work using friction-loss style inputs and outputs. It supports rectangular duct sizing by driving calculations from airflow and geometry constraints, then producing size selections and pressure-loss summaries.

The workflow centers on quick what-if iterations for duct runs and fittings rather than on importing complex projects from authoring tools. Cool Calc fits teams that need consistent duct sizing outputs with less setup than spreadsheet-driven calculations.

MEPWORK Duct Calculator sizes ductwork by calculating airflow and pressure losses from selected duct geometry and fitting inputs. It focuses on practical design outputs like duct dimensions, pressure drops, and equivalent length style adjustments used to account for fittings.

The workflow supports rectangular duct sizing decisions driven by aspect ratio and selected air velocity limits. Calculations align with common HVAC design practice by combining friction loss and fitting loss terms into a single pressure basis for balancing and checking runs.

Trane TRACE 3D Plus is a duct calculator workflow centered on HVAC design support that couples sizing outputs to ductwork geometry and layout decisions. The tool supports friction loss calculation and duct pressure class selection to keep pressure budgets and velocity constraints aligned with downstream balancing.

It also supports fitting loss coefficients through a built-in duct component library, which reduces manual coefficient lookup during iterative sizing. For teams producing documentation, it connects sizing results to deliverables like ductwork layout and associated construction details.