FAQ

License Activation

BurnSim runs unlicensed as a trial - up to 25 simulations per session, resetting every time you relaunch it, with no time limit on how long you can keep doing that. When you're ready to activate (see Activating BurnSim for the full walkthrough, including offline activation and moving to a new computer):

1. Open Help > Activate...
2. Enter the email address you purchased with (or your school email if you're eligible for the free .edu license - see below)
3. Leave the optional License key box blank unless you bought BurnSim through a reseller and were given a key - a purchase direct from burnsim.com doesn't use one
4. Click Activate

What happens next depends on your license status:

• Activation successful - you're done, BurnSim is fully licensed on this machine
• Check your email - a validation link was sent to the address you entered; click it, then reopen the Activate dialog (or click Activate again) to finish
• Email validated but no license found yet - if you just purchased, activation can take up to one business day to show up. If it's been longer than that, contact burnsim@burnsim.com
• Installs used up - your license's allowed number of installs has been used. Contact burnsim@burnsim.com to add installs or free up an unused one (e.g. after replacing a computer)

For anything activation-related that isn't covered above, contact burnsim@burnsim.com.

Purchasing & Downloading

BurnSim is $49. That is a personal license: non-commercial use by one individual. Purchase one at www.burnsim.com/purchase.aspx.

Using BurnSim commercially? Paid engineering, consulting, product development, research, testing, or other business use needs a commercial license - the personal and educational prices do not cover it. Details are coming soon; contact burnsim@burnsim.com in the meantime. The full terms for all three license types are on the License page.

.edu users get BurnSim for free - there's nothing separate to buy or redeem. Just activate (see License Activation above) using your school .edu email address and the license is issued automatically.

The latest installer and portable builds are always available from the download page.

Getting Started

New to BurnSim? Getting Started with a Basic Simulation walks through building a simple motor from scratch, start to finish. BurnSim Fields is the field-by-field reference for everything on the main window once you're past the basics.

Still Running BurnSim 3?

BurnSim 3 is retired. As of September 2026 it is no longer available for download and is no longer developed. If you already have it installed it keeps working, and your license still activates - but BurnSim 4 is where everything new happens, and it is a free upgrade for existing license holders: activate it from Help > Activate BurnSim with the same details you registered BurnSim 3 with. It installs alongside BurnSim 3 rather than replacing it, and leaves your saved motors and propellant database alone.

This wiki documents BurnSim 4. BurnSim 3's interface differs substantially - the old documentation is kept for reference under BurnSim 3 (Legacy).

Other Questions

Not seeing your question here? Contact burnsim@burnsim.com - this page will grow as questions come up.