Kerbal Space Program is a multi-genre game where players create their own space program.
User reviews: Overwhelmingly Positive (19,048 reviews)
Release Date: Mar 20, 2013

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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

"Early Access space ship building and simulation game, that combines challenge with humor. Fun, addicting, amazing community and mods to keep you busy."

Recent updates View all (15)

December 15, 2014

KSP has gone Beta! v0.90.0 is Officially Released!

Hello everyone and welcome to version 0.90.0 of Kerbal Space Program: Beta than ever!

Version 0.90.0 marks the transition from alpha to beta development of the game and will introduce the final major components to career mode. This then is the version that makes the game ‘scope complete’: every major feature that the game was designed to incorporate now exists and from here on, development will shift focus from implementating new systems to improving the existing ones, adding content, polish, balancing and bug fixing.

The update contains many new features and updates to previously existing systems which combined make for quite likely the largest update in the game’s three year history. Here are the highlights:

Upgradable Facilities
In career mode the Kerbal Space Center will advance with your space program. Start out with small buildings and limited functionality and build up your facilities into a state of the art space center with capabilities to launch and manage every mission you’ve ever dreamt of doing. Each building such as the Astronaut Training Complex, Vehicle Assembly Building and Tracking Station can be upgraded separately (and destroyed and repaired too), unlocking new and exciting capabilities and bonuses to your space program. Choose where you spend your money wisely: constructing buildings is most certainly not cheap.

Kerbal Experience and Skills
Your Kerbals now have specific skillsets they will develop as they gain experience: Choosing from your available applicants now mean deciding between pilots, scientists and engineers, each adding abilities specific to their skill, and unlocking further abilities as they earn experience by going on missions in outer space. Pilots are able to take over control of your spacecraft’s orientation to provide stability control during flight; Scientists are better at collecting and analyzing experiment data, so their science skills give bonuses to science collection, data transmission, and lab processing; and an experienced engineer can repair specific parts of your craft which may just save your mission.

Editor Overhaul
Ship Construction has been almost entirely rebuilt from the ground up. The Parts list now allows you tolook up parts not only by function (category), but also by resource, module type, tech level and much more. In case you want to add your own custom categories, that’s possible as well, you can set up lists of your favorite parts and organize your subassemblies into subfolders. As if that wasn’t enough there’s also the option to sort the filtered parts by mass, cost, size and name.

Also new in the Construction Facilites are the Gizmos which will allow you to Offset and Rotate parts, giving you complete control over how they are placed. The functionality to set a new root part for your craft has also been added, so you don’t have to rebuild your entire craft if you decide the root part should be somewhere else.

Other than these, we've also added many other improvements and new features: Symmetry can be toggled between Mirror and Radial modes, in both editors; Crew assignment is now fully persistent as you build; A new Stats toolbar panel lets you see your craft's total mass, part count and size; the list goes on.

Mk3 parts
After the major overhaul on Mk2 spaceplane parts in version 0.25 there is now a lot more to choose from when it comes to the Mk3 spaceplane parts: the old Mk3 parts have given way to a total of 15 all-new parts of unprecedented size, capable of carrying truly enormous payloads. Really. You can fit an orange Jumbo-64 fuel tank inside those cargo bays!

More contracts
Kerbal Space Program version 0.90.0 also brings the Fine Print mod by Arsonide into the game. This addition brings a whole new array of contract types to the table for you to choose from, adding depth and diversity to the contracts system. Survey areas, deploy satellites in precise orbits, capture asteroids, construct orbital space stations and build bases on planets or moons. This isn't a simple mod addition however. Fine Print author Arsonide has worked with us to tweak the mod into the stock game seamlessly. It’s all included and should provide any player with a challenge suited to their skill level and interests.

More biomes
The biomes system has seen a major overhaul for the first beta release of Kerbal Space Program. With help from KSP enthusiast and streamer Tanuki Chau every planet and moon in the game now has new biomes players can go out and explore. From the canyons of Dres to the peaks on Pol, the game now counts over 100 unique biomes. Each of these places represents another location where your Kerbals can gather, analyse, recover and send data from.

These are the major changes for Kerbal Space Program update 0.90. For everything else, check out the complete changelog here:

As always, the update is now available on the KSPStore and Steam.

We hope you will enjoy Kerbal Space Program: Beta Than Ever as much as we enjoyed making it.


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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 has different game modes, you can play the Career Mode if you want to expand and manage your own Space Center, taking on missions and researching new technologies. Or you can play Sandbox mode if you're only interested in flying and discovering the Kerbal universe without restrictions. There is even a mid point between these two, Science mode.

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.
  • 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 or 8 64 bit
    • Processor:Core i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:2 GB HD space
    • OS:Snow Leopard (10.6)
    • Processor:Intel
    • Memory:3 GB RAM
    • Graphics:SM3 512MB VRAM
    • Hard Drive:1 GB HD space
    • OS:Yosemite (10.10)
    • Processor:Intel Core i5
    • 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 i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:2 GB HD space
Helpful customer reviews
204 of 212 people (96%) found this review helpful
32 people found this review funny
422.0 hrs on record
Posted: March 22
Early Access Review
Hey, you!

Yeah, you!

Want to... Go to space?

Want to go to space, but accidentally end up going to the ground again, in pieces, get more determined and try again ten times until you can savour a brief victorious moment when you pass the threshold to the technical definition of space? Before the cruel gravity rudely yanks your creation back down towards physics emulated certain doom?

Want to "land" on a moon? Riddle your equatorial low orbit with tons and tons of debris?

Want to feel the bitter-sweet thriller-laced surprise of seeing your heartily built spacecraft perish in ways you never imagined possible, stretching your definition of failure to new horizons?

Want to...

Unwittingly run out of fuel and get stranded in an orbit painfully close to, yet unreachably far away from your intended destination, forcing you to sporadically architect and implement a quick rescue mission?
Only to resignedly succumb to the realization that your newly launched rescue expedition, due to inexplicably unfortunate circumstances, suddenly also finds itself in an immediate and dire need of yet another rescue mission?

Accidentally learn orbital and aerodynamic flight mechanics in your desperately frantic efforts not to explode, due to the game covertly being both inspirational and educational?

Have your spacecraft buggedly duplicate itself upon loading it, causing the freshly spawned evil twin clone from the dark abyssian realm of the Kraken to physically intersect with the unfortunate original craft, gleefully tearing it apart in a heartbreakingly horrendous show of telefragging, the likes of which you have not seen since playing Quake?

Curse your own careless inattention after painstakingly placing a small unmanned lander around an unexplored foreign moon of a newly discovered distant planet, readying it for the final descent stage when you discover that you have mistakenly attached an Argon gas tank to your Xenon gas powered ion engine?
Making the engine produce its simultaneously first and last soul tearingly choking sputtering sad noise before dying out, effectively sealing the fate of the lander to forever being an embarrassingly bricked monument to your own dementia?

Construct a fragile but vast interplanetary satellite communications network, precipitously vulnerable to periodic catastrophic cascading signal outages due to its many points of failure and lack of redundancy?

Pilot unproportionally enormous single staged space-planes all the way to other planets' moons and proceed to land on them in a frivolously flamboyant show of defiance against the confines of practicality, purpose and reason?

Want to...
Have your very distant, intricate and expensive spacecraft insolently threaten to violently wobble itself apart, for no reason other than purely in protest to all your meticulous and loving efforts of simply having created and cared for it?
While the craft wilfully ignores your all blood, sweat and tears from the strife of its arduous journey, as they silently boil away in the cold black emptiness of space?
With all the screaming impudence of a small child not having received the perfectly correct nuance of sugary flavour in its strawberry ice cream with colourful hello kitty sprinkles on top?

Yeah? Good, then the game is for you!

I can promise that you will have surprisingly much fun failing completely and miserably, compared to any other game, while the reward from the challenge of succeeding makes it all the more sweeter when you finally do succeed.

10/10, would launch again, for science!
Was this review helpful? Yes No Funny
117 of 125 people (94%) found this review helpful
36 people found this review funny
142.4 hrs on record
Posted: April 1
Early Access Review
1) Buy this game.

2) Build rocketship.

3) Accedently seperate boosters and deploy parachutes whilst still on laucnhpad.

4) Rebuild rocketship.

5) Fail to Escape atmospher

6) Crash

7) Rebuild rocketship.

8) Fail to achive orbit.

9) Crash

10) Rebuild rocketship.

11) Fail to achive orbit of the Mun

12) Abandon Kerbal and rocketship to drift in space forever without fuel.

13) Build new rocketship

14) Crash into the Mun.

15) Build new roecketship

16) Successfully get Kerbal to the Mun

17) Gather munrocks and plant flag

18) Get Kerbal back from the Mun, safly splashdown in ocian, recover craft.

19) Realise you have been playing for hours, learnt a lot about spaceflight and orbital mechanics, had a lot of fun and that your now realy good at building and flying spacecraft.

20) Attempt to build a spacestation, send probes or kerbals to other orbital bodies in the solarsystem, or design a working spaceplane.

21) Crash.

22) Rebuild Rocketship.
Was this review helpful? Yes No Funny
66 of 71 people (93%) found this review helpful
32 people found this review funny
32.1 hrs on record
Posted: April 9
Early Access Review
have major science test tomorrow
screw studying
play KSP for 12 hours
Test rolls around
Ace it with 105% (bonus points)
only person in school to do this
teachers asks how
say that Jeb helped me
she asks who Jeb is
look her in the eyes

he's a badass


No really. Get the game. It's amazing. (I acutally did ace that science test)
Was this review helpful? Yes No Funny
44 of 47 people (94%) found this review helpful
15 people found this review funny
1,025.9 hrs on record
Posted: April 1
Early Access Review
I liked the part about rockets

Was this review helpful? Yes No Funny
24 of 26 people (92%) found this review helpful
1 person found this review funny
29.3 hrs on record
Posted: March 22
Early Access Review
OMG this game is a masterpiece although its not finished yet. I have this game since the early access alpha and with every update you can see that the devs know what they are doing. You will fall in love with the Kerbals as soon as you set one of em up into your uniguely build Spacecrafts and fire it to the next planet. It is sooooooo much fun to see if your construction works out.

"The way is the goal" This game will give you great satisfaction if you like seeing how your plans unfold.
Also the game knows how to raise the difficulty bar 1 by 1. Beginners get a great introduction for a sandbox game and once your more of an expert and try out the ♥♥♥♥ load!!!! of great mods for it you will also be challenged by wanting more into Orbit (ISS setup, Docking ports, refueling stations, Lander-systems with rovers, name it)

No ♥♥♥♥, if i were to choose my top 5 games of over 700 atm i would pick this one for sure =D
THANK YOU SQUAD, keep it up
Was this review helpful? Yes No Funny
24 of 26 people (92%) found this review helpful
16 people found this review funny
9.6 hrs on record
Posted: March 26
Early Access Review
1 built a rocket
2 put jeb in it
3 got into space
4 jeb went for a space walk
5 accidently left hand on shift
6 jeb is the newest palnet orbiting the son
7 jeb hits the sun
8 let the tears flow (bagpipes play)
Was this review helpful? Yes No Funny
18 of 18 people (100%) found this review helpful
4 people found this review funny
530.8 hrs on record
Posted: April 10
Early Access Review
Simulators are often dumbed down, or complex to the point of absurdity.
KSP has a steep learning curve, but an easy interface.

I stayed up all night until my rocket could make it to orbit.
Lost many hours of sleep my first week of playing, getting to the moon.
Lost even more sleep, getting to the moon and back.
Lost more still docking for the first time.

And I don't want any of that lost sleep back, this game is WIN.
Was this review helpful? Yes No Funny
13 of 14 people (93%) found this review helpful
1 person found this review funny
256.5 hrs on record
Posted: March 28
Early Access Review
This is what a sandbox game should be. Start from nothing, and work hard learning how rockets work, and how rocket science and physics play a part in how your ships going to fly.

Put all that knowledge to good use and work to build a solid Rocket capable of flying all over the universe.

Then realize you did something incredibly stupid and crash on takeoff.
Was this review helpful? Yes No Funny
12 of 13 people (92%) found this review helpful
3 people found this review funny
156.4 hrs on record
Posted: March 27
Early Access Review
I like to use things learned from this game to baffle my friends.

Was this review helpful? Yes No Funny
10 of 10 people (100%) found this review helpful
209.1 hrs on record
Posted: April 4
Early Access Review
This game truly will rob you of every free moment you ever thought about having.

Your experience with this game is only limited by the capacity of your creativity.

I also want to credit this game for generating interest in a number of fields that young people these days need to be invested in. Engineering, Aerospace, Physics, Science, and many more.

Honestly its great to see a game be so fun AND genuinely thought provoking.
Was this review helpful? Yes No Funny
9 of 10 people (90%) found this review helpful
1 person found this review funny
126.6 hrs on record
Posted: April 2
Early Access Review
Am now qualified to join NASA.

Honestly though, this game is amazing! You learn so much about how space travel is done in the real world. This game has already taken so most of my playtime ever since I got it, and no doubt it'll continue to do so for a long long time. It's so fun to build your own aircraft, rocket, space station, rover, etc and make them work.

And when you ever get bored(which is not possible, but on the vigintillionth chance you do), you can look for mods that add parts or gameplay elements, having great modding support and an awesome community.

And this is still in beta, and looking at the developers, it can only get better.

If you ever get stuck from the steep learning curve, you can watch some tutorials done by Scott Manley.

Why are you still reading this? BUY IT NOW AND GO TO SPACE!
Was this review helpful? Yes No Funny
7 of 7 people (100%) found this review helpful
4 people found this review funny
37.2 hrs on record
Posted: April 5
Early Access Review
Built 10's of hundreds of different space planes, they all fail.

10/10 NASA wished they had my funding and expendable human resources
Was this review helpful? Yes No Funny
5 of 5 people (100%) found this review helpful
15.1 hrs on record
Posted: March 25
Early Access Review
Brilliant game!
Was this review helpful? Yes No Funny
6 of 7 people (86%) found this review helpful
44.5 hrs on record
Posted: March 30
Early Access Review
An amazing flight/space simulator, with amazing depth and detail, as well as vast scope. From building space-pleanes(and not-so-space planes), to hi-tech rockets to land on everything from the mun to Dres, as well as do orbital science, this game is a incredible space program simulator.
In addition, it is fully modable(and has a huge modding community with hundreds if not thousands of mods), and has cooperated with big-name groups like the ESA and NASA.
I highly recommend buying this, and i can only say, there is no such thing as to many struts, and check(and then RE-check) your stages. And then check them for a third time, just to be sure........

Easily, 11/10
Was this review helpful? Yes No Funny
4 of 4 people (100%) found this review helpful
1 person found this review funny
487.5 hrs on record
Posted: April 2
Early Access Review
I cried when I landed on the Mun for the first time.

Greattest thing ever.
Was this review helpful? Yes No Funny
3 of 3 people (100%) found this review helpful
44.8 hrs on record
Posted: April 4
Early Access Review
A must have imho. Great game, great mod communities. (/played around 2k 3k or more may be)

(source wikipedia: )

"The sections "Trivia", "Other Details", "Did you know? "," Quotes ", etc.
Squad working relationship with TeacherGaming company to develop a version of KSP specially designed for classrooms. This project, named KerbalEdu, aims to teach students the basic principles of physics, including gravity, and could be used to illustrate history courses on space conquest. A first draft was released in November 2013 in fifty schools, and should become available for all schools if the first tests are conclusive.

oh yeah it's totally neglectable at all xDr
Was this review helpful? Yes No Funny
3 of 3 people (100%) found this review helpful
83.6 hrs on record
Posted: April 15
Early Access Review
one of the best games ever for pc
Was this review helpful? Yes No Funny
3 of 4 people (75%) found this review helpful
1 person found this review funny
21.7 hrs on record
Posted: April 17
Early Access Review
Functional rocket Lego. Need I say more?
Was this review helpful? Yes No Funny
1 of 1 people (100%) found this review helpful
32.5 hrs on record
Posted: April 6
Early Access Review
I have played this game more than I would dare to admit. 30 hours on steam now, and probably another 200 before connected to steam. I like this game so much, because the developers alway come up with new stuff. I would definetely recommend this game.
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1 of 1 people (100%) found this review helpful
3.3 hrs on record
Posted: March 27
Early Access Review
a very great space travel simulator. i recomend it for everyone
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