PyroSim

subscription (annual) Engineer & Analyze

Fire dynamics simulation software that provides a graphical user interface for the NIST Fire Dynamics Simulator (FDS) -- used by fire protection engineers to model fire growth, smoke spread, sprinkler activation, and tenability conditions in buildings; imports CAD/BIM geometry (DWG, DXF, IFC), manages FDS simulations, and produces visualizations and reports; developed by Thunderhead Engineering (founded 1998, Manhattan KS).

Agent-hostile
3.0 /5 composite score
C1 4/5 reflects published annual pricing from USD 1,200 to USD 1,800 plus a 30-day trial, and RF2 keeps C2 1/5 because delivery is a desktop GUI with no public API or CLI. C4 4/5 reflects FDS-native workflows plus IFC, DWG, and DXF import with CSV and SMV export, and C5 3/5 reflects FDS and Smokeview integration.
Solid

Rubric Scorecard

How we grade →

Criterion Score Evidence
Value for the price 4/5 subscription (annual), from $1200 Source →
Agent Friendliness 1/5 API: none (desktop GUI only; scripting via FDS text input files)
Ease of adoption 3/5 --
Portability & lock-in 4/5 6 file formats
Interoperability 3/5 2 integrations

Pricing

Modelsubscription (annual)
Entry price$1200
Free tierno
Free viewerno
Trialyes
Billing unitper-seat
TiersNode-locked ($1200), Floating ($1800)
Visit PyroSim →

How we verified this: we checked PyroSim against its live site and an independent source — en.wikipedia.org. Nothing on this page is listed from memory. See how we grade. Verified 2026-07-05.

Evidence

File formats

FormatDirectionSupport
FDS native full -- Native FDS input format (.fds), the NIST open standard for fire simulation
IFC import partial -- BIM geometry import
DWG import partial -- CAD geometry import
DXF import partial -- CAD geometry import
CSV export full -- Results data export
SMV export full -- Smokeview visualization file

Integrations

FDS (NIST Fire Dynamics Simulator) (native) Smokeview (NIST visualization) (native)

Sources

Pricing

Alternatives in Fire & Life Safety

Smokeview
Free, open-source visualization and animation tool for displaying simulation results from NIST Fire Dynamics Simulator (FDS) and CFAST models -- renders particle flow, gas temperature contours, smoke density, and flow vectors in 3D animations and 2D slices, enabling fire protection engineers to understand fire and smoke behavior; developed and maintained by NIST.
3.8/5
Fire Dynamics Simulator (FDS)
Free, open-source computational fluid dynamics (CFD) model of fire-driven fluid flow that solves the Navier-Stokes equations for low-speed, thermally-driven flow with emphasis on smoke and heat transport from fires -- used by fire protection engineers worldwide to model fire growth, smoke propagation, heat transfer, and sprinkler activation in buildings; developed and maintained by NIST.
3.6/5
CFAST (Consolidated Model of Fire and Smoke Transport)
Free, open-source fire modeling software that simulates fire growth, smoke transport, and temperature distribution throughout building compartments during a fire -- used by fire investigators, safety officials, engineers, and architects to predict how smoke, heat, and harmful gases move and change as a fire progresses; developed and maintained by NIST.
3.4/5
MassMotion
Pedestrian dynamics and evacuation simulation software that models 3D crowd movement, circulation, and emergency egress scenarios -- used by fire protection and life-safety engineers to validate egress code compliance, analyze occupant flow under fire conditions, and optimize emergency response; features adaptive agent-based modeling, automatic way-finding, occupant demographics, and scenario testing; developed by Oasys (part of Arup).
3.2/5

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