Kerbal Space Program is a multi-genre game where players create their own space program.
User reviews: Overwhelmingly Positive (15,427 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

"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

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.


147 comments Read more

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.

170 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
519 of 561 people (93%) found this review helpful
73.1 hrs on record
Posted: December 1
Early Access Review
If I had this in 4th grade computer lab instead of Oregon Trail I would be an astronaut right now instead of dying of dysentry.
Was this review helpful? Yes No
262 of 266 people (98%) found this review helpful
Posted: November 23
Early Access Review
If you have a deep longing to attempt landing on the surface of a star, or the gumption to fling countless people into space without any consideration toward their lives, then this may be the game for you. Failure is the only option.

Most of your best stories will have nothing to do with what went right on a standard planet-to-planet maneuver, or how you really nailed that Hohmann transfer. No, it'll probably be the flaming wreckage you created where no one should have survived, but somehow did. My game once glitched as a Kerbal was falling from the upper atmosphere and he bounced on the surface. He bounced! And not in the crumpled heap of flesh and bone matter way. He bounced off the ground and appeared to be coming in for a graceful finish to a mission gone horribly wrong--the only type of mission that truly exists. He fell from space! And lived! Forget space, erect a statue!

My first manned mission to the Mun ended in predictable failure. I tried landing without any sort of landing gear. How, you might ask? By landing on the engine so it was primed for vertical takeoff. I forgot about my horizontal velocity, however, and ended up ripping the engine apart. I had all the fuel I needed for a return mission, but the broken engine was left kilometers away. Oops. At least I could plant a cool flag.

I attempted a rescue mission, because that is the first irresponsible thing everyone always thinks to do: stranded person in space? Send more people to help them! The first mission collided with the Mun at 600 m/s. Rough landing. The second mission landed, but I was probably 50km away--which isn't all that bad, all things considered. I had the stranded Kerbal run toward the landed ship, but it was taking forever. So I started using his little jetpack to expedite things. Lemons and lemonade. As it turns out, you can actually disintegrate a Kerbal if you get too much forward momentum and collide with something solid, like the surface of the Mun. You will forever be in our thoughts, Mac Kerman.

So much for the rescue. I may as well have the rescue team return safely. Remember that landing gear part? Yeah, I still hadn't updated that section of the ship. Instead I landed on my side and planned on using elevation as a natural ramp. Bulletproof logic. At least this Kerbal had the dignity of a fiery, fiery death. An honorable death. By my own hands.

In KSP, your little Kerbal guys can die and be listed in the ambiguous "Lost" column. It was with great sorrow that I saw Mac Kerman's name in there. I didn't care so much about the other guys. Who cares about the second guy on the Mun? But here's the thing, several years into my career mode Mac magically reappeared and was ready for action! He came back from the dead! And what was the first thing he wanted to do? Go back into space! To die again!

In conclusion, yes to this game. Just yes. I currently have a Kerbal orbiting the second moon, Minmus. Yes, he is in a stable orbit without a ship. Just him. And he's been there for close to 30 years now. I'll get around to that at some point.
Was this review helpful? Yes No
199 of 241 people (83%) found this review helpful
22.5 hrs on record
Posted: November 27
Early Access Review
For some weird reason, NASA doesn't think this game makes you qualified to work for them. >:(
Was this review helpful? Yes No
166 of 201 people (83%) found this review helpful
318.1 hrs on record
Posted: December 9
Early Access Review
I shot Jeb into space a while ago, I never saw him again.

I shot Bill into space to find Jeb...Bill now has an extreme case of sunburn...he is burning in the sun.

I shot Bob into space to avenge Bill...he was eaten by the Space Kraken.

10/10 Will space again.
Was this review helpful? Yes No
128 of 165 people (78%) found this review helpful
12.4 hrs on record
Posted: December 1
Early Access Review
I built my rocket wrong and it got stuck in the launch pad. One of the boosters broke loose and flew into the nearby gas tanks. The resulting explosion destroyed my entire rocket, the launch pad, and everything else. 10/10 would launch again.
Was this review helpful? Yes No
88 of 107 people (82%) found this review helpful
112.7 hrs on record
Posted: November 26
Early Access Review
This must be bought just for the mod potential.
Think it's too easy? Download some mods.
Think it's too hard? Download some mods.
Want to recreate Apollo? Download some mods.

One of the best sandbox games, because you can literally do ANYTHING!

Just Buy It. You will not regret it.
10/10 would explode again.
Was this review helpful? Yes No
68 of 77 people (88%) found this review helpful
5.6 hrs on record
Posted: December 12
Early Access Review
I've learned more about orbital mechanics in a few hours of playing this game then my entire life up to this point. Very cool.
Was this review helpful? Yes No
36 of 38 people (95%) found this review helpful
572.9 hrs on record
Posted: December 5
Early Access Review
This is one of the best games I have ever played. The game is flawless, and it only keeps on getting better. It is not even complete and it is worth every penny. Just wait for multiplayer and the thousands of customizable mods and you have a game that will entertain yourself forever. I have bought this game 3 times to give it out as a gift to friends because I love it so much. Please buy this game and experience the best game EVER!
Was this review helpful? Yes No
50 of 61 people (82%) found this review helpful
68.3 hrs on record
Posted: December 1
Early Access Review
Kerbals are fun to blow up.
Kerbals are fun to lose in orbit.
Kerbals are fun to throw into planets.
Kerbals are fun to strand on space rocks forever.
and yet, there is nothing more satisfying then getting one home safe.
I love this game
Was this review helpful? Yes No
124 of 187 people (66%) found this review helpful
35.0 hrs on record
Posted: December 1
Early Access Review
"Hmm, Kerbal Space Program seems like a fairly nice game."
- Downloads demo
"Oh wow, i gotta get this."
- Game is 30 bucks
"Damn i can't afford that."
- Downloads illegal version of game
"One day KSP, one day."
- A year passes
-Deletes illegal version of game
-downloads legit version
"I told you KSP, i'd never let you down."

Fact: true story.
Fact: I did not say those things
Fact: I might be lying.
Fact: this is a Fact
Fact: so many Facts
Fact: i did own a torrented version at one point and vow to replace it with legit version
Was this review helpful? Yes No
40 of 50 people (80%) found this review helpful
23.3 hrs on record
Posted: December 12
Early Access Review
I'll never forget what my estranged father said to me when he saw me playing KSP.

That's pretty cool...yeah.

Thanks Dad. Here look, you can see the orbit's

Oh, bye...
Was this review helpful? Yes No
24 of 26 people (92%) found this review helpful
283.2 hrs on record
Posted: December 4
Early Access Review
No review can summarize how unique KSP is! It is one of those games where you need to check the clock once in a while because if you don't, you will be seeing a lot of sunrises... Although mastering the game is a quite the challenge, the rewards are unique as this game will push you to learn several subjects ranging from physics to human values as you will experience Murphy's law in a whole new level.
Was this review helpful? Yes No
19 of 19 people (100%) found this review helpful
315.6 hrs on record
Posted: December 8
Early Access Review
To remove any doubts, this is by far one of the best space simulators out there.
The Good
  • Amazing learning experience
  • Choose where you want to go, with what, when, and how.
  • HUGE planets to discover, literally, thousands upon thousands of kilometers to walk, drive, or fly
  • Create awesome rockets, landers, bases on other planets, and spaceplanes, the way you want it
  • Fun science mode to work your way up, earning "science" in order to get better equipment and rocket parts
  • "Creative" mode where all parts are unlocked
  • "Career" mode for those really wanting a challenge (balance economy, science, and reputation for your own space organization
  • They are still adding to this game...
  • Many other great aspects to this game (however, this would be a long list with all of them)
The Bad
  • Graphics aren't the best, however, they are still pretty good.
  • Steep learning curve- It took me a while to learn to get to the "Mun." After this achievement, it was a lot easier to get to Minmus after this. It was difficult to get to Duna, however, once I got there, I have gradually learned enough to go pretty much anywhere and have recently made a permanent base on Laythe complete with science lab and crew pod, as well as a souped up Rover for them to drive. So basically, it takes time to get "good" at this game, but I assure you, it's rewarding.
  • not too much music (it's still good, just gets repetitive sometimes)
  • Getting to further out planets can take a long time, because it is difficult and takes more resourcefullness... (several hours if your like me and really take your time...)

Overall, this is a wonderful simulator offering a lot of real science with fun, providing lots of hours of engaging gameplay. Thank you for reading, and I hope this review helps. Feel free to leave a comment if you have any questions, I have over 300 hours logged and played the demo for several hours. I will try to get to them as soon as possible.
Was this review helpful? Yes No
17 of 17 people (100%) found this review helpful
116.7 hrs on record
Posted: December 15
Early Access Review
So much fun. If you like testing ideas and having fun with science, then this is your game.
Was this review helpful? Yes No
21 of 24 people (88%) found this review helpful
52.8 hrs on record
Posted: December 4
Early Access Review
One of those rare games that make you feel like YOU accomplished something. The first time I managed to land on the Mun was amazing, the first time I made it home after landing on the Mun is an achievement I will remember forever!

Ultimately the game still isnt finished yet...... but still really really good in sandbox mode, BUY IT!
Was this review helpful? Yes No
17 of 18 people (94%) found this review helpful
94.2 hrs on record
Posted: November 28
Early Access Review
This is seriously a fantastic simulator. I've spent entire days lost in it.
It says Early Access, but it's worth every penny in its current state.
By god just buy it.
Was this review helpful? Yes No
21 of 26 people (81%) found this review helpful
263.4 hrs on record
Posted: December 7
Early Access Review
Who needs a life anyhow?
Was this review helpful? Yes No
17 of 19 people (89%) found this review helpful
321.5 hrs on record
Posted: November 29
Early Access Review
Very good, Although it requires quite a bit of RAM to work--Especially if you want mods, which you should. But it has a good concept, teaches you more than you would expect, and is VERY funny.
Was this review helpful? Yes No
13 of 13 people (100%) found this review helpful
53.3 hrs on record
Posted: December 6
Early Access Review
I have been absolutely hooked to this game for over 2 years now. I do not have a lot of time to play, but when I do I find it beautifully inspiring.
Was this review helpful? Yes No
16 of 19 people (84%) found this review helpful
181.2 hrs on record
Posted: November 26
Early Access Review
ive had some bad experiences with early access games and told myself never again. my freinds however convinced me otherwise and im glad they did. this game is just about to enter beta, but it feels like a pretty solid game already. the gamemodes feel complete and the engine feels solid. ive had a tremendous amount of fun and have yet to explore all it has to offer. im currently in the process of trying to build a space station for refueling so my ships dont have to carry all the fuel for their entire mission from launch. im also trying to get my team thats on the "mun" home with all their science data intact (my design didnt include enough fuel to get them all the way back from the mun), so now im setting up a retreival mission. the game is merciless, but its realistically so, and i actually consider this one of its strengths. you learn something with every attempted mission. also, while the learning curve is steep, there are also tutorial missions that are actually very helpful. you can check them out right off the bat, or you can do like i did and blow up a few rockets first, but they are actually very helpful tutorials.
as good as it is its still an early access game and as such you can expect to encounter a few bugs and glitchs. the only bothersome one for me at the moment is that stage rockets that you release during launch disapear after a certain distance so you cant recover them for recycling. that said kerbal is one of the few games thats doing early access right. updates are fairly frequent and the developers pay attention to the communities comments and complaints. when an update causes an obvious annoyance thats easily fixable, theyll follow up shortly with a hotfix patch. I feel confident, based on the developers track record thus far, that during beta any issues that remain will be resolved and the game will receive the polish it deserves.
its also worth mentioning that theres already a thriving modding comunity for this game that adds additional features.
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