Welcome to the RAPTOR home page

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The content of this page in no way reflects the opinions, standards, or policy of the United States Air Force Academy or the United States government.

RAPTOR is a flowchart-based programming environment, designed specifically to help students visualize their algorithms and avoid syntactic baggage.  RAPTOR programs are created visually and executed visually by tracing the execution through the flowchart.  Required syntax is kept to a minimum.  Students prefer using flowcharts to express their algorithms, and are more successful creating algorithms using RAPTOR than using a traditional language or writing flowcharts without RAPTOR.

Click here to see a picture of RAPTOR.  For a paper describing the use of RAPTOR in a general education course, click here.


Where/how are you using RAPTOR?   I keep a list of what schools and universities are using RAPTOR and for what class.  This helps me plan future advancements.  Please email me and let me know.

Description: Description: Description: Download button NOTE! The installer was signed with a US Department of Defense certificate. You can get the root certificates from DoD Class 3 PKI Root Certificates. If you have difficulty with the signed installer, you can also try the unsigned installer.

Windows 8 users

You may need to enable .NET 3.5. See instructions here.

Portable Version

John Meir from Midlands Tech created a Portable App version (PortableApps.com). This allows RAPTOR to be used from a USB key or similar without installing. You can download the portable versionhere.

FALL 2014 VERSION (Updated 11 September 2014)

Only minor updates to include new signed installer

SPRING 2012 VERSION (Updated 13 September 2012)

13 September version fixes anomalies with set_precision

27 August version hopefully fixes Print Dialog on Windows 7 64-bit

Minor updates to Java code generation. Update to how RAPTOR OO mode handles recursive functions. Download here

KNOWN ISSUE: RAPTOR OO-mode does not correctly handle all recursive functions.

SPRING 2011 VERSION (Updated 18 May 2011)

You can get the Spring 2011 version (4.0.4) of RAPTOR from here (right-click and choose "save target as").  NOTE: See above on certificates. Also requires .NET 2.0 Framework.  Files generated in this version (except those in OO mode) can be opened with the Summer 2007 version.

NEW INSTALLER!  This installer has been tested on Windows XP SP3 (32 bit), Windows XP Tablet PC (32 bit), Windows 7 Professional (32 and 64 bit) and Vista Business (64 bit).  This installer should eliminate many installation bugs from the Microsoft Ink DLL.


Link to Older Versions

Other Operating Systems

RAPTOR is written in a combination of C# and A# (a port of Ada to the .NET Framework) and is only supported on Windows.  We have experimented with Mono Ubuntu.  We were able to get RAPTOR running on Ubuntu with some features removed.  Here's a zip with all of the files in case you want to try it. The most frequent question I get is if there is a Mac version. We don't have time to develop one, but I've heard that Wine may let you run the Windows version on a Mac.

About Modes

Did you know RAPTOR has modes?  By default, you start in Novice mode.  Novice mode has a single global namespace for variables.  Intermediate mode allows you to create procedures that have their own scope (introducing the notion of parameter passing and supports recursion).  Object-Oriented mode is new (in the Summer 2009 version)

About Loops

A common question is about RAPTOR loops being "backwards" from Java. We believe this form of loop logic is more intuitive to beginners; however, if you wish to match the semantics of Java loops, i.e. exit when the condition is false instead of when the condition is true, set the registry entry HKEY_LOCAL_MACHINE\Software\Raptor\reverse_loop_logic to true.

RAPTOR is Free!

RAPTOR is freely distributed as a service to the CS education community.  RAPTOR was originally developed by and for the US Air Force Academy, Department of Computer Science, but its use has spread and RAPTOR is now used for CS education in over 28 countries on at least 4 continents.

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OO Mode Handouts

Below handouts are by Elizabeth Drake, edited from Appendix D of her book, Prelude to Programming: Concepts and Design, 5th Edition, by Elizabeth Drake and Stewart Venit, Addison-Wesley, 2011. Linked here with author's permission.

For Faculty



Comments, suggestions, and bug reports are welcome. If you have a comment, suggestion or bug report, send an email to Martin Carlisle.


David Cox has put together a user forum at http://raptorflowchart.freeforums.org. This provides a place for users to exchange ideas, how tos, etc. Note however, that feedback for the author should be sent by email rather than posting on this forum.

Youtube Videos

Randy Bower has some YouTube tutorials at http://www.youtube.com/user/RandallBower. You can also search YouTube for "RAPTOR flowchart".


The UML designer is based on NClass, an open-source UML Class Designer.  NClass is licensed under the GNU General Public License.  The rest of RAPTOR, by US Air Force policy, is public domain.  Source is found here.  RAPTOR is written in a combination of A# and C#.  Unfortunately, I don't have the time to provide support on compilation issues.