Kerbal Space Program has left Early Access. 1.0 comes packed with new features, optimizations, bugfixing, and tons more! Conquering Space Was Never This Easy!
User reviews:
Very Positive (657 reviews) - 93% of the 657 user reviews in the last 30 days are positive.
Overwhelmingly Positive (31,066 reviews) - 97% of the 31,066 user reviews for this game are positive.
Release Date: Apr 27, 2015

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Recent updates View all (32)

June 21

Kerbal Space Program patch 1.1.3 is now available!

Hello everyone!

The 1.1.3 patch is now available! We’ve taken our time over the past couple of weeks to tackle as many issues as we could in this patch and the results speak for themselves: close to 100 fixes have been logged compared to the previous version of KSP, and we even found time to hide something small in the game that we’re sure a lot of long time fans will appreciate!

Check out the full changelog at our Forums.

283 comments Read more

April 30

Patch 1.1.2 is now available!

Hello everyone!

We noticed a number of issues persisted through the 1.1.1 patch earlier this week. We’re releasing patch 1.1.2 to address these issues before we head off to a long overdue vacation for the next couple of weeks. Patch 1.1.2 addresses issues with the user interface and landing legs, amongst others.

Check out the full changelog on our forums.

The Patch will start downloading through your Steam client automatically.

170 comments Read more

About This Game

In KSP you must build a space-worthy craft, capable of flying its crew out into space without killing them. At your disposal is a collection of parts, which must be assembled to create a functional ship. Each part has its own function and will affect the way a ship flies (or doesn't). So strap yourself in, and get ready to try some Rocket Science!

The game offers three gameplay modes: Sandbox, in which you are free to build anything you can think of; Science Mode, which lets you perform Scientific experiments to advance the knowledge of Kerbalkind and further the available technology; and Career Mode, in which you must manage every aspect of your Space Program, including administration strategies, Crew Management, Reputation, as well as taking up Contracts to earn Funds and upgrade your Space Center Facilities (or repair them).

Add to this the ability to capture asteroids (a feature done in collaboration with NASA), Mining for resources out across the furthest reaches of the Solar System, Constructing Bases and Space Stations in and around other worlds; plus literally thousands of mods from a huge active modding community, all add up into the award-winning game that has taken the space sim genre by storm.

Key Features

  • The Vehicle Assembly Building and the Space Plane Hangar allows players to build spacecraft out of any imaginable combination of parts.
  • Fully-fledged, Physics-based Space Flight Simulation ensures everything will fly (and crash) as it should.
  • Take your Kerbal crew out of the ship and do Extra Vehicular Activities.
  • Fly out to Moons and other Planets.
  • Procedural Terrain delivers detailed terrain at a vast scale. The Kerbal Planet is 600km in radius!
  • Mod-enabled, allows players to create new content and modify the game.
  • Ship systems. Keep an eye out for engine temperatures and fuel levels, and try not to explode.
  • Build ships with multiple stages, and jettison parts away as they burn out.
  • Full control over the ship’s setup allows for complex ships and advanced functionality.
  • Dock spacecraft together to build Space Stations, Massive Starships, or even surface bases on other worlds.
  • Manage your crewmembers, hire them, and send them out into space and make them into heroes.
  • Research and Develop new technologies to advance your Space Program.
  • Take on Missions to attract interest in your Space Program.
  • Discover new worlds and expand the scientific knowledge of Kerbalkind.
  • Extract valuable resources from all over the solar system.
  • And a whole lot more!

System Requirements

Mac OS X
SteamOS + Linux
    • OS:Windows Vista or 7
    • Processor:Core 2 Duo
    • Memory:3GB RAM
    • Graphics:SM3 512MB VRAM
    • Hard Drive:4 GB HD space
    • OS:Windows 8 or 10 64 bit
    • Processor:Core i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:6 GB HD space
    • OS:Mountain Lion (10.8)
    • Processor:Intel
    • Memory:3 GB RAM
    • Graphics:SM3 512MB VRAM
    • Hard Drive:4 GB HD space
    • OS:El Capitan (10.13)
    • Processor:Intel Core i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:6 GB HD space
    • OS: Linux (Most distros should work)
    • Processor: Core 2 Duo
    • Memory: 3 GB RAM
    • Hard Disk Space: 4 GB HD space
    • Video Card: SM3 512MB VRAM
    • OS:Ubuntu 14.04
    • Processor:Core i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:6 GB HD space
Customer reviews
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Very Positive (657 reviews)
Overwhelmingly Positive (31,066 reviews)
Recently Posted
( 225.3 hrs on record )
Posted: July 30
10/10 for complex sci-fi mod
wow much Physics
pls nerf solar sail mod
star citizen can thrust in atmosphere with Hall-effect thruster but you cannot in ksp
too realistic
must use hall-effect thruster in atmosphere to push a paper again
must go interstellar and build interstellar commsat network with lightyear signal delay again
Helpful? Yes No Funny
( 165.5 hrs on record )
Posted: July 29
This game is amazing. I could not recommend it more, just go ahead and buy it. Read the KSPedia first though, or explosions will be your best friend.
Helpful? Yes No Funny
( 9.6 hrs on record )
Pre-Release Review
Posted: July 29
dont like it
Helpful? Yes No Funny
( 231.7 hrs on record )
Posted: July 29
This game will teach you how to work at nasa. It is extremely based on engineering which is awesome! Totally worth the forty bucks.
Helpful? Yes No Funny
( 12.7 hrs on record )
Posted: July 29
Very good and challenging
Helpful? Yes No Funny
( 78.6 hrs on record )
Posted: July 29
No game has given me a greater sense of achievement...after thousands of attempts of pure utter failure.
Helpful? Yes No Funny
( 673.3 hrs on record )
Posted: July 28
Probably the best game I've ever played. It's extremely rewarding to learn about "rocket science," build cool ships, and plan elaborate missions.
Helpful? Yes No Funny
( 411.2 hrs on record )
Posted: July 28
I'm a old school rocket buff, I still launch rockets with my kids and I still have some old Estes rockets from when I was young. So of course I had to play this one. And I have to say I love it good fun, challenging too. I have played it many hours and still I have yet to land on every planet.

I hop they keep up with some addons or updates, lots of fun to play.
Helpful? Yes No Funny
Kamikaze Killjoy
( 106.2 hrs on record )
Posted: July 28
If you're looking to buy this game, and you're not sure. There's a few things things to keep in mind.

This game, Has one hell of a learning curve! Don't expect to be able to just start the game and be able to play. If you're having trouble. there are so many tutorials it's insane. Just keep in mind that there will be moments you will want to chuck your computer out the window. Totally fine. Just don't do that. But this game is a pain until you get the hang of it.

I suggest that you make your pyramid of rockets, laucn your kerbal into space, and lose him forever and later remember that his orbit is near your planet and you try a rescue mission. Just to fail again.
Helpful? Yes No Funny
( 777.2 hrs on record )
Posted: July 28
I have spent so much time on Kerbal Space Program. This is one game I keep coming back to after years of play. The sandbox nature of the game combined with the numerous parts available leads to endless possibilities for Rockets, Planes, Space Probes, Boats, Trucks, Cars, and really anything you can think of. Take the base game and add mods like Infernal Robotics and Tweakscale and you have so much more to do. Then add an additional 150 mods from CKAN and there is literally no end to what can be accomplished. 10/10
Helpful? Yes No Funny
Most Helpful Reviews  In the past 30 days
105 of 108 people (97%) found this review helpful
20 people found this review funny
1,167.0 hrs on record
Posted: June 30
This game has one of the steepest learning curves of any game i've ever played, but it has also given me the greatest feeling of achievement from any game i've ever played.

When you land on the Mun for the first time, after mashing buttons trying to stabalise your craft and you barely make it due to the lack of fuel, there's no better feeling than knowing you have to do it all again and launch a rescue mission. (or you could just leave Bob there for science).....

I am a big fan of space, physics and science in general and playing this game has been an education for me. Because of KSP I have watched dozens of YouTube videos on astrophysics and aerodynamics I would have probably never watched without this game and learned a ton of interesting things, and i love that.

The game has a fantastic modding community with a huge variety of mods to add realism or give your game a futuristic sci-fi feel. A favourite mod of mine is 'Remote tech', I don't play without it.

This game produces some stunning visuals too as you drift through the vast openness of space, orbiting moons, chasing asteroids, collecting science and designing planes, rockets, trucks, rovers, probes, boats even helecopters and mech walker/transformer type sh** thanks to mods...

If you ever look up at the stars and wonder what it would be like to go there..... Well, this is as close as i'm ever gunna get.
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99 of 101 people (98%) found this review helpful
26 people found this review funny
65.3 hrs on record
Posted: July 6
After my son had a really bad day where nothing seemed to go right, we had a talk about how failing is part of learning.

I said "Remember how you watched me flying rockets on the computer?"

He said "Yeah, they kept going all over the place and smashing into the ground! Have you landed on the moon yet?"

"Nope. Crashed into it a couple times. Learning new things every time though."

"Can I play that game too!?"

-Kerbal Space Program: Lessons for life.
Was this review helpful? Yes No Funny
106 of 116 people (91%) found this review helpful
197 people found this review funny
168.9 hrs on record
Posted: July 2
Still haven't successfully returned from anywhere but Minmus and the Mun.
RIP Jebediah I
RIP Jebediah II
RIP Jebediah III
RIP Jebediah IV
RIP Jebediah V
RIP Jebediah VI
RIP Jebediah VII
RIP Jebediah VIII
RIP Jebediah IX
RIP Jebediah X
RIP Jebediah XI
RIP Jebediah XII - Jebediah MMMMCMLXVII

Was this review helpful? Yes No Funny
72 of 74 people (97%) found this review helpful
30 people found this review funny
180.2 hrs on record
Posted: June 30
I bought this game after trying the demo and having a lot of fun with it. I've played KSP off an on for a few years. The game has a very active mod-making fan base and this opens up a lot of new avenues for play. My best review of this game is anecdotal. (I sent this to a friend when I was only a few hours into play. I had no mods installed and was still very much learning the basics. Anyone who plays KSP might find this story relatable.)

"One of my test flights put 3 Kerbals into orbit. They were low on fuel so I did a retrograde burn to bring them home. Except that I didn't do a retrograde burn, I did a prograde burn. By the time I realized it, I had burned too much fuel to get them home. I reduced their orbit as much as possible, even using all available monopropellant from the thrusters. They were stuck in an elliptical orbit over 100km from the surface at their lowest point. With no way to return to the surface under their own power, I had one option; a rescue mission.

I built a new ship, one with sufficient fuel to achieve orbit and maneuver to intercept the lost ship which I dubbed "Lost Eagle." Lost Eagle had been fitted with docking collar and I guess that was just fate because it was now my goal to use that in the rescue effort. The rescue craft went through several iterations and multiple aborted attempts at rescue. The final design of the craft contained a single seat cockpit and a 4 seat hitchhiker pod which was used for it's relatively low weight. This would end up being the ultimate design flaw. It was my goal to grab the 3 stranded crew members, and transfer the rescue pilot to the pod before re-entry.

Docking is hard. I would say impossible but I've seen videos of people doing it and I know it can be done. But despite many hours and multiple misses. I had got Rescue 1 and Lost Eagle lined up next to each other about 200 meters away. I closed enough distance that I felt it would be close enough to 'jump.'

The first crew member from Lost Eagle jumped from his old ship to the new one. It went pretty smoothly, but in the process the ships drifted further apart. I did a corrective burn on Rescue 1 to get them closer together and jumped the second crew member. Success again. 1 left. He jumped, this time from the furthest gap. He too arrived successfully. I felt a rush of success, a feeling of accomplishment frequently lost in today's video games. Plenty of fuel for the retro burn. They were coming home. This process had taken hours and this was the payoff that would make it worth while.

The design of the re-entry craft was basically a can that held 4 crew with 4 radial parachutes coupled to a single seat inline cockpit with a shielded docking collar on the tip. She wasn't pretty, but she was light and efficient. The plan was to transfer the pilot to the reentry craft before they hit atmosphere, but I had discovered that I couldn't deploy the parachutes from the re-entry craft. It was a problem I had known about since earlier iterations of the craft but I was willing to work around the problem by deploying the chutes without decoupling the cockpit. The whole thing still landed successfully in my tests.

At 5000m above the surface, having survived re-entry. I pressed the spacebar to activate the chutes. I don't know if I double tapped it or if I had just had my staging backwards, but when I hit the space bar the cockpit split off from the hitchhiker can. Knowing full well that there was nothing I could do to save the pilot of Rescue 1 I watched in horror for a second as it hurtled to the ground with no possibility of survival. I quickly switched to the other part of the ship. I tried manually clicking on the parachutes to deploy them. The hitchhiker module contains nothing but chairs. No controls that could be used to deploy the chutes. Again I watched in horror as the 3 rescued kerbals hurtled towards their doom, the exile in orbit seeming to be safe alternative to the instantaneous death that awaited them at hundreds of meters per second.

The game would have let me revert to the launch of the mission, or even the assembly area where I could have redesigned the rescue craft that had doomed these 4 brave kerbals. I chose not to. I was angry at myself for the mistake. I had invested so much time into this and laziness had prevented me from fixing what I knew was a flawed design. The empty ship, Lost Eagle remains in its orbit a floating monument and constant reminder to any Kerbal that looks up, that taking the easy path or acting haphazardly can have terrible results. I will be reminded of this every time I play the game."

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40 of 50 people (80%) found this review helpful
16 people found this review funny
1,126.5 hrs on record
Posted: July 12
Why are you still reading reviews? Buy this game!
Was this review helpful? Yes No Funny
20 of 21 people (95%) found this review helpful
18 people found this review funny
62.6 hrs on record
Posted: July 22
After 60 hours:

-Can't oribit properly.
-Can't get to the mun.
-Can't do anything.

I love it. 10/10
Was this review helpful? Yes No Funny
16 of 18 people (89%) found this review helpful
16 people found this review funny
201.7 hrs on record
Posted: July 11
Unsteadily launched a capsule into orbit, completed an orbit burn, did an EVA, got some science, prepared for re-entry, pitch, roll, turn to distribute the heat evenly on the heatshield, before the dawning realization hit -- I forgot the chute.

RIP Jebediah Kerman.

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15 of 17 people (88%) found this review helpful
2 people found this review funny
22.0 hrs on record
Posted: July 1
A game for those with a more creative mind set. Set a goal and feel great once you hit it. Landing on the moon for the first time by yourself is as close to nirvana as you will get outside of finally downing that dark souls boss you couldnt beat.
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12 of 12 people (100%) found this review helpful
2 people found this review funny
336.7 hrs on record
Posted: July 14
Kerbal Space Program

I started off with this game quite some time ago, back in the days when Kerbin was still neon green and all the fuel tanks were an ungodly blue color. I feel like the time has finally come for me to offer some decent feedback on this title, so that others know what to expect.

This game isn't very impressive visually, and while its art style is mostly consistent that doesn't change the fact that it suffers from both somewhat low resolution textures and a general lack of detail. For example, the lack of settlements on the Earth-analogue planet. I won't criticize it too heavily, though. While orbiting a planet or moon, the game does shine quite nicely - literally, as the sun rises over your celestial body of choice. Despite its flaws, it definitely gets the job done better than its closest relative Orbiter, and one should keep in mind that it is an indie title. There's enough detail here to be satisfied, and that's without installing modifications.

The in-game audio design is decent, but it gets repetitive eventually. The explosions are particularly satisfying. The music is calming, but also gets extremely repetitive after some time. I would suggest modifications, or to mute it and put your own music on instead. There isn't a ton to talk about here.

This game's performance has improved considerably lately. Previously, I would've had a bone to pick with Kerbal Space Program, but it has made a turn for the better in the past year or so. It still won't run on just any PC, but even unimpressive laptops can run it on low settings fairly comfortably. I should note that performance is highly dependant on what is currently happening in-game. If you construct a large ship, the framerate will drop due to physics calculations. Also, the newest version of the game has some issues with regards to bugs and glitches, so you might want to wait for another patch or else revert back to an earlier version via Steam Beta.

This title is in a league of its own with regards to gameplay. I'm still not sure that I've ever played anything like it. It features (mostly) realistic orbital physics and revolves around a sandbox building experience where you construct virtually anything - ranging from space shuttles to fighter craft to rovers... even to boats - out of rocket and aircraft parts. Some people will spend all their time using aerodynamics mods to create realistic aircraft designs, others will recreate historical rocket missions. Some might colonize another planet, and others might just spend most of their time crashing into the ground or fumbling as they try to understand how space really works. No matter what you like doing, there's almost certainly something for everyone with Kerbal Space Program. In my opinion, the only game that comes close to rivaling this title's gameplay is Orbiter, and that title is a much more in-depth space flight simulator that does not allow building your own ships out of different parts. Note that the game has no multiplayer as of this review's publishing.

Community Content
This game is absolutely phenomenal with its community content. From its humble beginnings, the aeronautical parts in-game were directly inspired by a modification, and the author of that mod was later hired by Kerbal Space Program's development team. There are now mods for everything. Realistic aircraft engines. Weaponry, ranging from machine guns to ballistic missiles. Careful recreations of historical spacecraft. Complete remakes of the physics system to be extremely realistic. In-game computer systems that will do things for you. Audio and visual modifications that completely change how the world looks. And, of course, complete overhauls to the Solar System, bringing things to the scale of real life. The game doesn't even have multiplayer, and someone took the time to code a fully functional mod to make it happen. The possibilities for community-driven content are endless in this game, and more is created every day.

This game is a perfect example of everything right in PC gaming, and is probably one of my favorite titles on Steam. I gained a better understanding of orbital physics from it than I did by reading about orbital physics in textbooks and encyclopedias, and I still marvel at all the possibilities in this game. It is simply incredible how it has progressed from its Early Access days, and despite its flaws, and the questionable decisions made by its publisher, it is a fantastic title that I recommend everyone try.

I recommend Kerbal Space Program.
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12 of 15 people (80%) found this review helpful
18 people found this review funny