Version 2.0 · Apache 2.0 · Free Forever

Process Simulation.
No License Required.

ChemForge is a full-featured chemical process simulator that runs entirely in your browser. Build flowsheets, solve flash and distillation problems, run sensitivity studies — all without installing a single program or paying a license fee.

Launch Free Demo View on GitHub

No install required Runs 100% locally Data never leaves your machine

app.chemforge.net

ChemForge GUI — flowsheet simulation canvas

Click to open the live demo — free, no sign-up

Why ChemForge

Built for Engineers, Not IT Departments

Everything you need to model a process — none of the overhead of enterprise licensing, annual renewals, or IT approval tickets.

Runs In Your Browser

No installer, no .NET runtime, no IT ticket. Open a URL and you're simulating. ChemForge uses WebAssembly to run all thermodynamic calculations locally — no cloud, no latency, no data exposure.

Your Data Stays Private

Every calculation happens on your machine. Your process data, flowsheet designs, and chemical compositions are never uploaded to a server. Work on sensitive projects with full confidence.

Open Source Core

The full simulator is open source under Apache 2.0. Inspect the thermodynamics, extend the unit operations, fork it for your research. No black-box vendor lock-in.

Steady-State & Dynamic

Run steady-state simulations and transient dynamic analyses in the same environment. Flash separations, rigorous distillation columns, pump curves, controller tuning — all included.

Sensitivity Studies

Sweep any parameter across any unit operation and plot the effect automatically. Understand how feed temperature, pressure, or composition changes propagate through your entire flowsheet.

Custom SVG Symbols

Design your own P&ID symbols with the built-in SVG editor. ChemForge uses standard engineering symbols out of the box, and lets you create custom ones for your specific equipment.

Unit Operations

Everything in the Toolbox

ChemForge ships with a complete library of unit operations for steady-state and dynamic process simulation.

Flash Drum (VLE)

Distillation Column

Heat Exchanger

Pump

Pipe & Fittings

Mixer

Splitter

Tank (Dynamic)

Stoichiometric Reactor

Component Separator

Sensitivity Study

Controller

TPxy Phase Diagram

Graph Display

Inlet / Outlet

P&ID Symbols

Getting Started

From Zero to Simulation in 60 Seconds

No setup wizard. No license activation. No training course required before your first run.

Open Your Browser

Navigate to app.chemforge.net or self-host the open-source version. No download, no install, no account.

Build Your Flowsheet

Drag unit operations onto the canvas, connect streams, configure temperatures, pressures, and compositions in plain engineering units.

Run and Analyze

Hit Run. ChemForge solves your flowsheet, displays stream properties, generates plots, and lets you sweep parameters in a sensitivity study.

Comparison

The Right Tool for Most Engineers

ChemForge covers the steady-state and dynamic workflows that SMEs, startups, and academics actually use day to day.

Feature	ChemForge	Aspen Plus / HYSYS	ChemCAD
License cost	Free (Community)	$25,000–$55,000 / yr	$5,000–$15,000 / yr
Installation required	✓ Browser only	✗ Windows installer	✗ Windows installer
Runs offline / 100% locally	✓	~ Requires license server	~ Requires license server
Data privacy (no cloud upload)	✓	~ Depends on deployment	~ Depends on deployment
Open source	✓ Apache 2.0	✗	✗
Steady-state simulation	✓	✓	✓
Dynamic / transient simulation	✓	✓ (separate module)	~ Limited
Rigorous distillation (VLE)	✓	✓	✓
Sensitivity / parameter sweep	✓	✓	✓
Specialty modules (amines, HF, etc.)	✗ Not yet	✓	~ Add-ons available

Aspen and ChemCAD are trademarks of their respective owners. Pricing estimates based on publicly available information as of 2026.

Pricing

Start Free. Scale When You Need To.

The core simulator is free and open source forever. Pro adds cloud convenience and priority support for teams that need it.

Community

$0 / forever

Full simulator, open source, no account required. Download or use the hosted version.

✓ All 15+ unit operations
✓ 51 MB chemical property database
✓ Steady-state & dynamic simulation
✓ Sensitivity studies
✓ Local save / load (JSON)
✓ Apache 2.0 — fork & modify freely

Launch Free App

Pro

$12 / month

Cloud convenience, extended data, and priority support for professionals and small teams.

✓ Everything in Community
✓ Cloud save & sync across devices
✓ Flowsheet version history
✓ Extended property data (electrolytes, polymers)
✓ PDF & Excel report export
✓ Priority email support (48 hr SLA)

Coming Soon

Enterprise

Custom

On-premise deployment, SSO, custom property databases, and dedicated support for larger organisations.

✓ Everything in Pro
✓ On-premise / Docker deployment
✓ SSO / LDAP integration
✓ Custom property database uploads
✓ Dedicated support SLA
✓ Training sessions

Pro payments processed securely via Stripe. Cancel any time. · Self-host the open-source version at no cost.

Process Simulation.No License Required.