The best replacement for kerbal space program is space engineers.

The best alternatives to kerbal space program are rated as following:
★★★★★  space engineers

Your alternative for kerbal space program is not listed? Suggest!
Speaking about kerbal space program, one probably shouldn't forget about joystick.

Other search terms related to kerbal space program and their ratings are:
★★★★★ joystick
You have in mind a companion for kerbal space program and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of kerbal space program in all years. Click on graph for more.
kerbal space program
space engineers