Below are links to software that will help you design, build, and fly your rockets.

RockSim is one of the most widely used sport rocketry design programs.  You can design your rocket, select your motors and simulate the flight to make certain your rocket is stable before you build and fly.

SpaceCAD is another rocket design and simulation program

OpenRocket is another rocket design and simulation program – and it is free!

Winroc is a suite of programs that includes an altitude calculator, CP (Center of Pressure) calculator, thrust curve manager, and graphing – and they are free!

Software Lists – Other web sites have extensive lists of rocketry related software:
  ASTRE – this club web site from New York lists software packages they have found useful
  NAR lists several software packages on line available at no cost has an extensive list of rocketry software available on line