Kerbal Space Program is a multi-genre game where players create their own space program.
User reviews: Overwhelmingly Positive (18,661 reviews)
Release Date: Mar 20, 2013

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Early Access Game

Get instant access and start playing; get involved with this game as it develops.

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 (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.


233 comments Read more

October 7, 2014

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.

202 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 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
51 of 54 people (94%) found this review helpful
6 people found this review funny
56.3 hrs on record
Posted: March 6
Early Access Review
1) Made first rocket. didn't know Bob was aboard. Crashed, no parachute. Bob survived.
2) Second rocket had parachute. Parachute deployed when rocket took off. Lots of pretty corkscrew contrails in the sky. Rocket crashed. Bob survived.
3) Third rocket was a repeat of second rocket. Still hadn't learned.
4) Fourth time everything worked and Bob still survived.
5) Several rockets later I reached low orbit. Beautiful!
6) Enjoying the game very much.
Was this review helpful? Yes No Funny
35 of 38 people (92%) found this review helpful
4 people found this review funny
412.1 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
44 of 54 people (81%) found this review helpful
14 people found this review funny
1.7 hrs on record
Posted: March 14
Early Access Review
If I was in charge of Nasa everyone would be dead by now.
Was this review helpful? Yes No Funny
28 of 29 people (97%) found this review helpful
2 people found this review funny
511.8 hrs on record
Posted: March 12
Early Access Review
I absolutely love this game. When I first started playing however, I did not. I kept hopping in for an hour or so and attempted to play, never getting much done. This went on for the first 30-40 hours I played the game. In theory it seemed like a cool game I would like, but I could not get past the learning curve with my limited playtime.

Finally I quit playing an MMO and really sunk my teeth into KSP. With the help of Scott Manley and his amazing tutorials I started to really understand what in the world I was doing.

After my tutorial spree I spend time playing with different mods and ultimately unlocked the tech tree in science mode. Then for the first time I played in career mode. For me it was a different spin on how I played and it hooked me back in again.

As of now, I can send spacecraft to other planets, land on them, do some science, and return to Mother Kerbal without killing anyone (usually).

If you think you might like it, try the demo, watch some of Scott Manley's tutorials, check out the KSP subreddits, but most importantly give yourself some time to know what in the hell you are doing!
Was this review helpful? Yes No Funny
11 of 12 people (92%) found this review helpful
7 people found this review funny
61.6 hrs on record
Posted: March 5
Early Access Review
I bought this game during one of the Steam sales a year or so ago. I did not start playing until 3 days ago. After 3 days playing, I'm at 21.7 hours.

-Am I playing because I couldn't attend Space Camp back in the day?
-Am I playing because I'm still waiting for NASA to give me a response to the Astronaut application I sent them?
-Am I playing because the Johnson Space Center in Houston has blocked me from attending "Meet an Astronaut Friday"?
Yes, but please don't tell the authorities!

Great game!
You get to build your own space craft, satellite, Lunar Lander. You can go to the Mun!

Honestly, one of the best things about this game is the fact that you can build your own space craft and THEN optimize your craft to try and conquer the galaxy. A problem solving game at it's finest!
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8 of 9 people (89%) 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
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7 of 8 people (88%) found this review helpful
70.0 hrs on record
Posted: March 20
Early Access Review
Rocket Science! Explosions! Fun!

Kerbal Space Program (KSP) puts you in charge of a space agency (think NASA) whose goals are... actually that's pretty much up to you. The game's career mode will give you missions you can accept, such as "get a rocket into orbit" or "land on the Mun (Moon)," and you get rewards for doing so such as research points to unlock more modules, prestige to do... stuff, and monies to pay for things. But really you can do whatever you please. And outside of career mode which structures your objectives and gameplay to an extent is a sandbox mode that lets you do as you please without worrying about unlocking things or having money for them.

The game basically has two main aspects (three if you include the Career Mode stuff described above): building stuff to send into space, and then launching that stuff and making it do other stuff. Designing successful rockets (and later on spaceplanes) can be a bit difficult, since you have to worry about stuff like the weight, the power of the engines, maneuverability, and more. The 1.0 Update plans to add a tool that will let you see potential problems with your designs before you actually try them out, but until then you basically just have to wing it and hope that your designs don't crash or explode in a spectacular manner.

Once you have your designed rockets (or spaceplanes), then you get to launch them and perform whatever "mission" you have chosen for yourself. You have to fly the craft yourself, which often requires great precision and timing. Assuming you don't just crash and die horribly, your biggest concern is fuel, and running out of it at a bad moment can make you go back down towards the planet (you did attach a parachute, right?) or leave you drifting in space unable to return home unless you can find some way to rescue them.

This is not an easy game even on easy difficulty settings, but it is one that can give a real feeling of accomplishment when you make successful designs, achieve your first orbit, make that fateful landing on the Mun, and much more. It gives you an appreciation for the difficulties that real world space agencies face when planning or performing such missions.

At the time of writing, KSP is still in early access, though its full release is not too distant. Regardless, this game is fully playable now and stands as one of the best early access games ever to make it to Steam. If you are interested in Science, and specifically space exploration, then you really should check this game out. Actually... if you like games period you should try this out. There is a demo, though it is of an older version of the game and therefore has far less than the main game does.

Difficult, often frustrating, and yet an excellent game that makes you feel great when you succeed at something in it. :3
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6 of 7 people (86%) found this review helpful
1 person found this review funny
8.1 hrs on record
Posted: March 10
Early Access Review
Kerbal Space Program is an amazing game. It is very hard to learn, but once you finally understand the mechanics, it gets fun. But while you are trying to learn, have fun building crazy ships that will inevitably crash and kill all kerbals.
11/10 IGN
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7 of 9 people (78%) found this review helpful
1 person found this review funny
12.1 hrs on record
Posted: March 16
Early Access Review
This game taught me everything I know about orbital mechanics and spaceflight. Easily my most favorite game ever,
Was this review helpful? Yes No Funny
7 of 9 people (78%) found this review helpful
1 person found this review funny
14.5 hrs on record
Posted: March 17
Early Access Review
Do you wish for an opportunity to explore the universe without having to worry about your resources being eaten away by the government's new healthcare system?

Then this game is the game for you.
Was this review helpful? Yes No Funny
4 of 4 people (100%) found this review helpful
37.5 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
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6 of 8 people (75%) found this review helpful
25.9 hrs on record
Posted: March 9
Early Access Review
An imaginative and original simulation game that will spark the creativity of both adults and children. The slearnign curve is a bit sharp, but your failures are rewarded with catastrophic explosions. The only downside to Kerbal is that it is terribly unoptimized and even high-end computers struggle to keep up with the inefficiency of design. This is due to the game being made within Unity, a fairly new game development engine that requires little programming knowledge to get into.

I give this game a 7/10. It would recieve a 10/10 if only the developers built their own engine for optimization purposes. A game like this should really be able to run on a modern medium-grade laptop, but it simply cannot in it's current state.
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3 of 3 people (100%) found this review helpful
3 people found this review funny
1,022.1 hrs on record
Posted: April 1
Early Access Review
I liked the part about rockets

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3 of 3 people (100%) found this review helpful
2 people found this review funny
255.0 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.
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3 of 3 people (100%) found this review helpful
2 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)
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6 of 9 people (67%) found this review helpful
1 person found this review funny
24.3 hrs on record
Posted: March 8
Early Access Review
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2 of 2 people (100%) found this review helpful
49.2 hrs on record
Posted: March 8
Early Access Review
I just love this game. Its great to see things go boom, and even better when you actually acomplish something
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2 of 2 people (100%) found this review helpful
1 person found this review funny
156.5 hrs on record
Posted: March 8
Early Access Review
Move over NASA Scientists. I've crashed enough little green guys into the moon to know how to do this ♥♥♥♥
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2 of 2 people (100%) found this review helpful
128.4 hrs on record
Posted: March 27
Early Access Review
I like to use things learned from this game to baffle my friends.

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2 of 2 people (100%) found this review helpful
15.3 hrs on record
Posted: March 6
Early Access Review
Unlimited amounts of stuff to do in this game and with mods there's even more than unlimited.
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