Try & Buy

The single-user implementation of PFM, Tetra SDM version 3.5.0, is available for download and purchase.

SDM Demo SDM Personal SDM
Alternatives up to 10 up to 10 unlimited
Criteria up to 15 up to 30 unlimited
Load/Save no yes yes
Import/Export no no yes
Price FREE+ $USD 400* $USD 800*


+Tetra SDM Demo does not require activation.
*Prices are in US dollars or equivalent and are subject to change without notice.

To download and install Tetra SDM, click the “download” link on this webpage, save the file, and double-click the file to install Tetra SDM. To activate the non-Demo features of Tetra SDM, you will need to purchase an activation code.

To purchase an activation code, click the appropriate “Buy Now” button on this webpage. You will be redirected to PayPal’s secure shopping website where you will be asked to complete the purchase. Your activation code and instructions on registering your copy of Tetra will then be provided to you by email within 24 hours.

Please note that you must enable cookies for in order for the “Buy Now” links to work.

Upgrades from Tetra SDM Small Decisions to Tetra SDM are also available, as is Tetra GDM, the multi-user implementation of PFM. For more information, and educational pricing, please contact



NEW: On Neural Network Training Algorithms

Spectrum and Optimization Algorithms

Supply and Demand Equilibrium and Debreu’s Theory of Value

Economic Theory’s Curves

Demand, Barter, and Exchange

The Foundations

Decision Theory

Utility Theory


Download Tetra

Tetra Quickstart Guide

Tetra Online Documentation


Numerical Mathematics


An Elementary Demand Theory Error

Ordinal Utility and Indifference Curves

Von Neumann's Error

Game Theory: Whose Values?