Kerbal Space Program is a multi-genre game where players create their own space program.
User reviews: Overwhelmingly Positive (14,111 reviews)
Release Date: Mar 20, 2013

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Early Access Game

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Note: This Early Access game is not complete and may or may not change further. If you are not excited to play this game in its current state, then you should wait to see if the game progresses further in development. Learn more

What the developers have to say:

“KSP is still under development. This means the game will be improved on a regular basis, through updates that add new features, content and bug fixes, so make sure to check back for new versions.

The game is being built as a sandbox first, so there are no objectives yet, but we want you to try it out and have fun with it already. You're free to build anything you can think of, and there is an entire Solar System to explore.

During development, KSP is available for purchase at a discounted price, which will gradually increase up to its final retail price as the game nears completion. So by ordering now, you get the game in its current state, and you'll get all future updates for free.”
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Recommended By Curators

"Do you like making things go fast? Is "this obviously needs more rockets" something you say on a daily basis? Then get KSP and launch some Kerbals!"

Recent updates View all (14)

October 7

Kerbal Space Program: Economic Boom is Now Available for Download!

Kerbal Space Program, the award-winning, indie space agency sim game from Squad, released its latest update, Economic Boom, and it is available to play today.Updates are free to existing players. KSP: Economic Boom offer new players the most fully-realized version of the game, which is still in active development for PC, Mac and Linux as an Early Access title on Steam and via the game’s website.

Players will experience a new challenge as the Kerbal Space Center, where players build and launch their rocketships, is now fully destructible. Buildings can be decimated by poorly-steered rocketships and in the game’s Career Mode, require costly repairs for players trying to manage their space agency.

Among these buildings is the new Administration Facility, in which players can select and activate Strategies. The Strategy system is a new gameplay mechanic, where each strategy, once accepted, applies effects over several game aspects, specifically Kerbal Space Program’s three in-game currencies, Funds, Reputation and Science. Some examples include:

  • Aggressive Negotiations: Enables players to get a discount on the cost of parts but at a cost to Reputation on each ‘discount’
  • Open-Sourced Technologies: Divert Science earnings to make them public domain, increasing Reputation.
  • Unpaid Intership Program: Boost your Science earnings without spending any Funds by hiring unpaid interns to do the data crunching. Working for the Space Program surely is its own reward, isn’t it? Well, as long as an agency’s Reputation lasts that is.

Career Mode is getting a significant addition with the Administration Building and all that comes with it,” Felipe Falanghe, Kerbal Space Program creator and lead developer said. “The Strategy system gives players great freedom to change the rules around, and ultimately it allows them to tune the game to fit their own ways of playing. Also, as it’s fully moddable and new strategies can easily be added, this new feature has a lot of potential for expansion.

The team also worked with modder, Christopher “PorkJet” Thuersam, to incorporate his popular SpacePlane+ parts pack mod to the game. This was more than a simple addition however: Each part was updated for even better looks, and to offer players parts that are there not just specifically for spaceplanes, but that can be used in as many combinations as possible.

The game is now available for 40% off on STEAM and the KSP STORE.

148 comments Read more

July 25

0.24.2 Hotfix Patch Released

Hi again,

I'm sure most of you have noticed a mildly infuriating bug related to right-clicking parts after yesterday's patch... So did we. It was fortunately a simple fix, and we've got a hotfix patch available now.

Here's the changelog:

============================ First Contract (v0.24.2)


* Fixed a critical issue which prevented opening the right-click menus for several parts.

As always, the latest version is available on the download page at the KSPStore, or an automatic update will be headed your way if you're on Steam.

Happy Launchings,


57 comments Read more
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About This Game

Kerbal Space Program is a multi-genre game where players create their own space program.

In KSP, you must build space-worthy craft, capable of flying your 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 is being built first as an open sandbox, you're free to build anything you can think of, and fly it wherever you want, even into orbit and out to other planets and moons throughout the Kerbal Solar System. The first draft of the career mode is also available now, it is still in development, so expect more features!

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.

Planned Features

  • Take on Missions to attract interest in your Space Program.
  • Discover new worlds and expand the scientific knowledge of Kerbalkind.
  • And a whole lot more!

System Requirements

Mac OS X
SteamOS + Linux
    • OS:Windows Vista
    • Processor:Core 2 Duo
    • Memory:3 GB RAM
    • Graphics:SM3 512MB VRAM
    • Hard Drive:1 GB HD space
    • OS:Windows 7
    • Processor:Core i3
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:2 GB HD space
    • OS:Snow Leopard
    • Processor:Dual Core Intel
    • Memory:3 GB RAM
    • Graphics:SM3 512MB VRAM
    • Hard Drive:1 GB HD space
    • OS:Mountain Lion
    • Processor:Core i3
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:2 GB HD space
    • OS: Linux (Most distros should work)
    • Processor: Core 2 Duo
    • Memory: 3 GB RAM
    • Hard Disk Space: 1.5 GB HD space
    • Video Card: SM3 512MB VRAM
    • OS:Ubuntu 14.04
    • Processor:Core i3
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:2 GB HD space
Helpful customer reviews
149 of 154 people (97%) found this review helpful
532.0 hrs on record
Posted: October 31
Early Access Review
3... 2... 1... Aw shi-

If your parents have ruined your life by pumping your head full of overt positive reinforcement of all the great things you will accomplish in life, and have a shrine of your Academic Team, Little League and Girl Scout trophies and awards, and you live in the shadow of their crafted image of potential you know you will never fulfill, then KSP is for you.

You will spend hours engineering great and mighty rockets, planning to launch humble little Kerbals (in game human analogs, because kerploding simulated HUMANS isn't politically correct in gaming unless it's portrayed in war, murder mysteries, alien invasions, war, zombie horror, war, armed rebellion stories, humorous ciminal empire sandboxes, war, over the top armed racing games, war, Valve circlejerk physics engine display pieces, war, or the kitchen sink) into space...

Wait. What was I saying? Oh, right, you slap random aeronautic components with names longer than a West Coast Rapper's discography (what did you think I was going to say?) and plot a course for the very stars themselves! And then promptly cry tears of relief that your parent's were always wrong about you, and you actually CAN'T do anything right, all along - when you realize you forgot to put adequate battery banks on board, so now your little astronauts are floating through the hostile void forevermore, committed to the lonely depths of space, never to set foot on green Kerbin again. THIS. IS. YOUR. FAULT.

Just kidding.

They kerploded on the launch pad like your freshman fall semester career plans when you realized "Intro to College Biology" was the EASIEST class your degree required. But it doesn't matter, because trial and error in this game is so much fun, you'll completely forget about your dead end job and/or unemployment!

But getting to the meat and potatoes of the game, you have about 15-20 celestial bodies to explore, and all the components you need to get there, not to mention very easy to add mods to fill in any gaps in equipment. Each body, moons, planets, even the local star can be explored and your engineering options are endless.

One can make: crappy unmaned probes, crappy unmanned rovers, crappy space stations, crappy single stage to orbit launch vehicles, crappy shuttles, crappy rockets, crappy planetary bases, crappy space boats, for the odd moon with liquid surfaces. The possibilities are as countless as the stars, in that, the number could probably be calculated, but if you spent time doing it, no woman will ever touch your pe-

Moving on. KSP is hours of fun, offering both structured career mode, and stupid anarchist sandbox mode for rebellious teens that hate rules. The game is still in development as of this review, and thus new content is constantly being added, not that there is any lack of stuff to do - KSP is massively replayable and tremendously enjoyable.

Final score: 293/299 superfluous boosters.

Protip: This game currently constitutes the entirety of the Democratic Peoples Republic of Korea's space program, despite the state's lack of hardware capabe of running it, even with its undemanding specs.
Was this review helpful? Yes No
205 of 231 people (89%) found this review helpful
4.3 hrs on record
Posted: November 8
Early Access Review
6 Banned words in the NASA : "It worked in Kerbal Space Program."
Was this review helpful? Yes No
165 of 204 people (81%) found this review helpful
629.9 hrs on record
Posted: October 30
Early Access Review
-Build $400,000,000 ICBM
-Lands on Kerbal
-Missile in ruins all over KSC
-best use of taxpayer's dollars since ebola
Was this review helpful? Yes No
61 of 66 people (92%) found this review helpful
364.9 hrs on record
Posted: October 28
Early Access Review
Kerbal Space Program is great fun.
If you love space and explosions, this one comes highly recommended.

A lot of potential players express concern at the complexity of the game, but they needn't worry if they're really interested in playing. KSP is a game first, and a simulation second. You don't have to be Scott Manley, or even average, at the game in order to have fun. Just build stuff and fly it about! You'll learn the nuances of spaceflight as you go. Not to mention if flight and orbital mechanics elude you, there are mods such as MechJeb that assist you with flying your ship and going from one planet to another, or perform the maneuvers FOR you, that way you can focus on building and watching things go boom. The more recent addition of "Career" mode takes the new player experience even further, serving as a guided, but still sandboxy, introduction to all aspects of the gameplay.

Reasons to buy KSP:
  • You like space.
  • You like explosions.
  • You like sandbox games.
  • You have a soul.

Reasons not to buy KSP:
  • You mistakenly think space isn't awesome.
  • Explosions scare you.
  • You're afraid you'll get sand in your eyes.
  • You have no soul.
Was this review helpful? Yes No
31 of 32 people (97%) found this review helpful
118.3 hrs on record
Posted: November 5
Early Access Review
Half flight simulator, half sandbox game and half space exploration; it makes 1,5 and this game counts more than just 1.
My best money spend so far.
You can explore from purple to green planets, from exploding on launchpad to crashing into sun, for making rockets like nasa, well, flights are less like nasa, your rockets will be more like ''manned cruise missiles''.
There's not a single thing that you can cannot explore. I learned a lot about orbits and physics, you'll realy feel like a real space engineer (or an idiot) after playing this game.
It is simulator, but not boring simulator like other simulators, it is very exciting in every mission you launch is unique (except routine flights to spacebases).
10/10, would buy again if had enough money
Was this review helpful? Yes No
33 of 38 people (87%) found this review helpful
31.9 hrs on record
Posted: October 24
Early Access Review
When i was a child i dreamt of being a NASA engineer. Turns out i slacked off too much at school. Ah well. But i always had an interest in space, and particularly exploring it.
This game gave me a sandbox to play in where i could design spacecraft and send little green men up into space above the blue earth... erm, i mean Kerbin.
You know its always the little green men trying to visit earth in the movies. In this they cant get away quick enough.

You know this game has something for everyone. Even if you do not have any real inclination to do anything so involved as perfect orbits, or landing perfectly on the moon (Mun) or whatever this game still gives you the chance to make crazy rockets that you can set off and see how far they get before it, and its possible inhabitants die a horrible, horrible death.
And for those, like me who have a more involved interest in the subject matter, there is plenty that will satisfy you.

Think you can do it better than NASA? Give it a go.
For the price, you get a lot of play hours, and even some replayability.
Check out the mods, also.
Was this review helpful? Yes No
87 of 129 people (67%) found this review helpful
13.1 hrs on record
Posted: October 24
Early Access Review
This game got me a job a NASA.
Was this review helpful? Yes No
36 of 50 people (72%) found this review helpful
693.7 hrs on record
Posted: November 6
Early Access Review
Do you have autism for space?
Sure, we all do.
Buy this game today. Why are you even thinking about it? You have already logged 600 hours pirated. Go. Go.
Was this review helpful? Yes No
13 of 14 people (93%) found this review helpful
81.0 hrs on record
Posted: November 1
Early Access Review
One of the most addictive and exciting games I've played in recent memory and that although it is not even in beta stage yet. So wonder what is more to come from this. But if you like Space games, like building rockets or space planes and send them out to explore the universe this is definitely the game to get. Even after over 30 hours of playing I still scratched on the surface. I wished this is what Spore space stage should have been. With Kerbal Space program you could lots and lots of fun in this one, but beware this can be a real time sink. I also recommend watching some of the tutorial videos online to help a bit with frustration at the beginning when you just don't get your rocket into orbit!
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11 of 12 people (92%) found this review helpful
451.7 hrs on record
Posted: November 9
Early Access Review
At this point I have dumped 445 hours into this game, and I don't regret a single minute of it. I absolutely love this game even though I can still be considered bad at it. But that is exactly why this game is fun. No matter how good you get someone else will show you something simple and it will just massively expand gameplay options for you. I would recommend this game to anyone that has any interest in space travel. As far as I'm concerned this game does it the best.
Was this review helpful? Yes No
13 of 16 people (81%) found this review helpful
11.1 hrs on record
Posted: November 7
Early Access Review
Kerbal Space Program is a fun and exciting sandbox game where you can make rockets, fill them with kerbals and shoot them into space. Its and game jammed packed with hours of entertainment and loads of explosions!
Was this review helpful? Yes No
13 of 16 people (81%) found this review helpful
162.3 hrs on record
Posted: November 16
Early Access Review
A very small price to pay for a lifetime of entertainment.
Was this review helpful? Yes No
13 of 17 people (76%) found this review helpful
84.7 hrs on record
Posted: October 31
Early Access Review
If you like building things to fly in space then get this game! 10/10
Was this review helpful? Yes No
9 of 10 people (90%) found this review helpful
7.3 hrs on record
Posted: November 6
Early Access Review
This is an absoloutely amazing game that is so good I wouldn't know it was an Early acess if it didn't say it in big letters at the bottom of the store page. My only critism, the game has now become to intesive for my computer and I am getting a new one just for this game.
Was this review helpful? Yes No
10 of 12 people (83%) found this review helpful
15.7 hrs on record
Posted: October 30
Early Access Review
Jebediah Simulator 2037

Was this review helpful? Yes No
12 of 16 people (75%) found this review helpful
684.9 hrs on record
Posted: November 12
Early Access Review
>Built a large space station that took 12 hours to make.
>Add engines.
>Attempt to go to Duna in it.
>Station falls apart and causes Kessler effect.
>Kerbal breathes heavily.
>Lands safe in tiny command pod.
>Debris tracker is full.

2/10 will build a second station.
Was this review helpful? Yes No
8 of 9 people (89%) found this review helpful
172.9 hrs on record
Posted: November 1
Early Access Review
modsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmodsmods boom. You just blew up your space station with a rocket to the Mun. Or you deorbited your space station for no reason with the solar panels open because you like seeing them break apart. Maybe you just made a cargo plane, uh oh, a wing broke off. Fast forward 10 years later. You have conquered the solar system with the help of (mods) and now you have relay satellites beaming back and forth across the solar system with probes and space stations orbiting every celestial body and bases with kerbals falling on their faces on Duna and Eve. Because space is great. And so is this game. Mods.
Was this review helpful? Yes No
9 of 11 people (82%) found this review helpful
424.4 hrs on record
Posted: November 7
Early Access Review
I lost my life
Was this review helpful? Yes No
10 of 13 people (77%) found this review helpful
5.9 hrs on record
Posted: October 25
Early Access Review
Great game, fantastic physics engine.

Its very easy to pick up and start playing, with quite a long learning curve, which can get as complex as you want it to really.
Was this review helpful? Yes No
6 of 6 people (100%) found this review helpful
45.6 hrs on record
Posted: November 11
Early Access Review
[EARLY ACCESS REVIEW] KSP is a challenging space-sandbox simulation game.

+Vast open area (space) to play in
+Highly detailed planets
+Amazing customization for the space planes/rockets
+Detailed base for launches.
+Complex physics
+Nothing is easy (might be a con for others)
+Cool easter eggs here and there. (Space kraken, monoliths, pyramids, etc.)
+Science and career mods are amusing (I prefer science)
+Highly detailed UI, but fairly easy to learn.
+Mod support
+Cheat tab (ctrl+alt+f12)
+Kerbals, they add some comedy to the game, and are just great in general.
+Out of spaceship walking is fluid and smooth
+Graphics are great.
+Regular updates, keep the game new and fresh
+Able to speed up time (this prevents the game from getting boring most of the time)
+First person cockpits are a nice addition to the game
+Controls for the spaceships/planes are nice
+Animations are excellent
+Graphics options are detailed
+Well optimized
I could name more, but I think I'll stop here.

-Occasionaly glitchy and sometimes crashes (but this doesn't matter that much since it's in Early Access)
-No steam workshop (there is so many mods already, and it is so easy to install them, adding Steam Workshop support to the game would be amazing)
-Price is a little high
-sometimes you cannot speed up time in certain areas, which causes the player to wait 10 minutes just to get to the interesting parts of the game.

Overall, KSP is a excellent game, and I see a bright future ahead for the developers and the game.

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