Kerbal Space Program has left Early Access. 1.0 comes packed with new features, optimizations, bugfixing, and tons more! Conquering Space Was Never This Easy!
User reviews:
Very Positive (640 reviews) - 93% of the 640 user reviews in the last 30 days are positive.
Overwhelmingly Positive (31,688 reviews) - 97% of the 31,688 user reviews for this game are positive.
Release Date: Apr 27, 2015

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Recent updates View all (35)

October 11

Kerbal Space Program update 1.2 “Loud and Clear” is now available!

Hello everyone!

Kerbals hit a milestone, they are now interconnected and they can hear you Loud and Clear! Let your imagination fly with new possibilities, build communication networks, control vehicles remotely and explore every inch of the Kerbol System in ways that weren’t possible before with this new update!

Kerbal Space program 1.2: Loud and Clear includes a broad range of improvements and features that will enrich the overall game experience, such as the introduction of CommNet and KerbNet, a rewrite of the Stability Assist System (SAS) that makes your launches more accurate and fuel efficient, an engine change from Unity 5.2 to 5.4, more tweakable options for many parts, a complete fuel system redesign, and much more!

Here are some of the highlights for this update:

Set up your own communications networks and have better control over your probes even when they cannot establish a direct connection. Link your probes back to Kerbin via an antenna to be completely autonomous and build relay networks for better science transmission!

Use satellites for reconnaissance purposes, scan the terrain below you, find biomes and anomalies, and place custom waypoints with a targeting interface.

Improved Fuelflow System
The Fuelflow system has been rewritten and now you have total control over how the fuel flows through your vessels!

Improved Wheels
The stability of Wheels has been greatly improved. Your rovers, wheeled vehicles will now turn and handle smoothly, making the overall driving experience more pleasant. Aircraft are also more stable, and all wheels have realistic load limits.

You can find the complete changelog here.

Kerbal Space Program 1.2 Loud and Clear is now available on the KSP Store and on Steam, and will soon be available on other third party platforms.

228 comments Read more

September 13

Update 1.2 Pre-release is here!

Hello dear Kerbonauts!

Update 1.2 has finished its Experimentals phase and we’re excited to announce the launch of the Public Pre-release.

During Experimental testing a small team of experienced KSP players threw everything they’ve got at the game in order to help us catch as many bugs as possible, so that we could make the game as stable as it could be. Now we’re proud to say that’ve come to the point where we can finally release the open test build.

This ‘pre-release’ test build is for everyone to have a go before we officially released the update and you’ll be able to opt-in to get the Pre-release builds via the Steam betas, or, for the first time ever, through the KSP Store. Naturally, you’ll need own a copy the game beforehand in order to access these builds. This opt-in branch will run for a minimum of two full weeks before the release date of the final update (the final release date hasn’t been closed, so changes may occur).

To facilitate discussions of the Pre-release branch we’ll be opening up a temporary sub-forum for feedback. Additionally, a Pre-release project will be made available on the bug tracker to report bugs on.

Furthermore, we want to help the modding community by making the modding API public. Click this link and enjoy!

Finally, and as promised, you can get Porkjet’s awesome rocket parts package files here .

We’re almost there and we couldn’t be more excited. Stay tuned for updates and happy launchings!

366 comments Read more

About This Game

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

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

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

Key Features

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

System Requirements

Mac OS X
SteamOS + Linux
    • OS:Windows Vista or 7
    • Processor:Core 2 Duo
    • Memory:3GB RAM
    • Graphics:SM3 512MB VRAM
    • Hard Drive:4 GB HD space
    • OS:Windows 8 or 10 64 bit
    • Processor:Core i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:6 GB HD space
    • OS:Mountain Lion (10.8)
    • Processor:Intel
    • Memory:3 GB RAM
    • Graphics:SM3 512MB VRAM
    • Hard Drive:4 GB HD space
    • OS:El Capitan (10.13)
    • Processor:Intel Core i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:6 GB HD space
    • OS: Linux (Most distros should work)
    • Processor: Core 2 Duo
    • Memory: 3 GB RAM
    • Hard Disk Space: 4 GB HD space
    • Video Card: SM3 512MB VRAM
    • OS:Ubuntu 14.04
    • Processor:Core i5
    • Memory:4 GB RAM
    • Graphics:SM4 1GB VRAM
    • Hard Drive:6 GB HD space
Customer reviews
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Very Positive (640 reviews)
Overwhelmingly Positive (31,688 reviews)
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25,229 reviews match the filters above ( Overwhelmingly Positive)
Most Helpful Reviews  In the past 30 days
227 of 266 people (85%) found this review helpful
227 people found this review funny
1,431.8 hrs on record
Posted: September 28
Just remember to eat and drink occasionally.
Was this review helpful? Yes No Funny
93 of 96 people (97%) found this review helpful
5 people found this review funny
469.6 hrs on record
Posted: September 25
Kerbal Space Program, at least to me is the king of simulation games. While I play numerous others (such as Farming Simulator) they don’t seem to hit every mark in that field. KSP, while challenging at first is the one that throws everything that happens in reality at the player, and force them to deal with it. While a game like Farming Sim only really requires you to keep an eye on fuel or some crops, KSP requires that you maintain a healthy supply of necessities ranging from fuel and electricity, to a satellite connection back home. But the part of the game that truly shines is the feeling you get when you first land on the Mun. A friend who gave the game a shot said
“it was just...pride. So many Kerbals died in previous attempts, and I finally made it.”

While the game is difficult, I can’t stop asking people to try it. To me, it’s the perfect “life isn’t about the destination, but the journey” and I think this game captures that perfectly.
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19 of 21 people (90%) found this review helpful
2 people found this review funny
119.6 hrs on record
Posted: September 25
If you have even a remote interest in space and space travel, buy this game. Seriously. It's worth it.

There's a learning curve but when you learn how to play, it's very satisfying and rewarding completing contracts and exploring the solar system.

There's a huge modding community as well so you can make the experience even better with Realism Overhaul & Real Solar System to get as close to real life rocket ships as possible. (+hundreds of other mods like SpaceX rockets and other real life rockets and engines and graphic improvement mods.)

Seriously, this is one of the best games I've ever played. The development team (SQUAD) is very active and transparent with the community.
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12 of 14 people (86%) found this review helpful
1 person found this review funny
231.8 hrs on record
Posted: September 23
This game is pretty perfect. Don't buy it if you expect a story or an immersive career mode. Do buy it if you want to spend hundreds of hours building realistic-style rockets and trying to fly to the Mun, other planets and their moons, etc... and exploding spectacularly TONS of times.

A++ game
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5 of 5 people (100%) found this review helpful
395.7 hrs on record
Posted: October 3
This is probably, my favorite game ever.
Its the only game that after a while I miss the ambiance, the music, the sounds and simply have to get back to.

I suck at it, its very hard to master (if its ever possible) but its simply great.

I could not recommend it more
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4 of 4 people (100%) found this review helpful
1 person found this review funny
257.3 hrs on record
Posted: September 25
Ok, first step... Build rocket, watch it explode.
Second Step: Build rocket again, launch it, then watch it dive bomb into the ground/water/mountain....
Third Step: Build rocket again, launch it, make it to the upper atmosphere and discover you didn't bring enough fuel....
Fourth: Build rocket again, add more fuel, launch, and finally get it into orbit.....
Fifth Step: Pass out from high blood pressure attack from actually getting into orbit and finding out you don't have enough fuel to return to the planet....

Sixth Step: Look at the clock and discover you forgot to go to work, feed the cat, ect.
Seveth Step: Return to step 1.

Bloody love this game! I acutally have more hours than posted, as I play this game on my laptop while on the road, usually at night so that I'm all stressed out.

Now the Cons:

[ ] Steep learning curve, unless you have high understanding of physic's, math, your already an Astronaut.
[ ] An i5 Intel CPU (or AMD equal) or better recommended
[ ] Lots of memory and graphics memory
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4 of 4 people (100%) found this review helpful
1 person found this review funny
178.2 hrs on record
Posted: September 25
This game is amazing. There was a bit of a learning curve to figuring out the specifications needed for a space ship to reach its target, but with a little reasearch on orbital mechanics and rocket design, designing rockets became easier. It's such a satisfying feeling when you finally acomplish missions that took hours of hard work, I've even had to pull out the old pen, paper and FE approved calculator a few times while playing this game.
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21 of 37 people (57%) found this review helpful
42 people found this review funny
406.4 hrs on record
Posted: September 23
After over 300 hours ofplaying, this game crashes the most on my computer. I just recently had a game crash, and the window that said "KSP.exe has crashed" had crashed, then the window that said that last window crashed, then crashes.
Would crash again
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3 of 3 people (100%) found this review helpful
404.3 hrs on record
Posted: October 6
Perhaps the greatest space exploration game there is

Author's note: Upon reaching 100 hours in this game, I decided to write a lengthy review. Recently, however, I reached another milestone in the form of 400 hours. As such, I felt that the time was ripe to write a new, better review.

I was born on the exact same day as the Mars Polar Lander was to touch down on the south pole of Mars. This NASA probe was going to broaden our knowledge of the red planet - not unlike countless other probes that had already visited - but this was, regrettably, not to be. Prior to landing, an error caused the craft to crash into the Martian surface at a high speed.

Errors like this are common in Kerbal Space Program as well. We all know how it is: You've sent a lander-type probe or capsule through the Kerbol system, and at last, the target is right below you - be it the Mun, Duna, or any other solid object. At some point, you discover that there's not enough juice. Or not enough electricity to keep the baby under control. Or that there is enough fuel - but only for a landing. Which is fine if it's an unmanned probe, but good luck if you have three unlucky Kerbals on board. It's a good thing they cannot die of thirst, hunger, exhaustion or boredom.

The interesting thing about KSP, however, is that these errors do not matter. You might have an impressive explosion on the launch pad, a complete failure while trying to leave the atmosphere, or a more annoying error - like the fact that your fancy satellite doesn't have enough batteries, or that you forgot to bring science instruments. But guess what? This game encourages you to try again. If you fail in this game, it will not shove you into a ditch and laugh. Rather, it will help you back up and tell you what went wrong. In Kerbal Space Program, it is quite simple to spot errors by experiencing them. And then, it is equally simple to fix that error with a small upgrade - say, an improved booster, or some extra batteries. Eventually, new problems will appear - and you fix those too. And through this trial and error, you get the perfect rocket at last.

This is where the game suddenly becomes truly magnificent. For quite a lot of time, I didn't have any idea how to get my crafts into orbit. So I created a proper rocket, tried to figure out what went wrong the last times, modified the rocket accordingly, and then gave it a shot. Minutes later, a satellite is safely in orbit around Kerbin, telling me interesting things about the atmosphere and cheerily transmitting signals down to the surface.

Obviously, I got a massive confidence boost because of this. You can probably guess what happened next: I put together a Saturn V-ish rocket and tried to send some (un)lucky Kerbals to the Mun. It didn't go as planned, to say the least: They all ended up burned or exploded, mostly the latter. So guess what I did? I went back to the drawing board, created a better rocket, took it through extensive testing, and then the day came. It was my own July 1969. Jebediah and Bill were now Neil and Buzz. And guess what? The Kerbin flag was planted firmly on the Mun, and my brave little Kerbonauts returned as heroes, becoming the public favorite for a future mission to Duna. But that's another story.

Moving on from stories of trial, error, success and joy, it's time to look at what the game has to offer. As you've probably guessed by now, it's about building rockets and sending them into space. The wide range of parts, physics, planets and celestial objects allows you to create your own little NASA. Probes, space stations, capsules, landers, rovers and airplanes are all possible to design and cr- fly as you please.

Why the "Kerbal" in the name? Well, this game takes place in a fictional planetary system with smaller planets, moons and distances. The Sun is named Kerbol, and orbiting it is Moho (basically Mercury), Eve (basically Venus), Kerbin (basically Earth, with humans being replaced by green-skinned, adorable Kerbals), Duna (basically Mars)...Yeah, you get the idea. The game has lots of planets and moons to visit, most of which are fully explorable.

The game modes? You got three different modes, suited for different playstyles. Sandbox is simple: No progress, credits or reputation (we'll get back to that), but every rocket part and all upgrades available at no cost. If you enjoy building whatever you want with no consequences, Sandbox is fitting. Next out is Science. It works similarly to Sandbox, but with another interesting factor: You have to research and unlock new rocket parts by doing science. "Science" can be anything from taking a ground sample outside of your local space centre, or landing a rover on a distant planet to do geological surveys. The more interesting, the more science.

The final mode is Career. In this mode, it's money-earning time. You start off as a small space agency with sheds instead of hangars and no capability to reach space whatsoever. So what do you do? There are three things that you need to focus on. First of all, science - we've already gone through that. Second, money. This is self-explanatory; earn money, buy rocket parts, build bigger and more expensive rockets, and upgrade your facilities - but how to earn money? This is where Reputation comes in.

To put it simple: You earn Reputation by doing cool stuff and not messing it up - take a tourist into space, land a probe somewhere, et cetera. If you do mess up, you lose Reputation. Here's the fun part: Higher reputation means better Contracts. There are plenty of corporations that are willing to give you some money if you can satisfy their demands. Complete a contract, and get more Reputation, Science and money. Fail a contract? Yes, you guessed correctly.

Now let's move back to space exploration. Let's say that you've done all your preparations, signed the necessary contracts, and launched some nice stuff into space. You got some satellites here and there, and even some Kerbals screaming for help at the Munar surface (let's pretend you have a rescue ship underway). Now what?

Well, there's mods. This is one of the many areas where Kerbal Space Program really shines - mods. The game has an active, engaged modding community, and you can find a mod for just about everything. There's a mod that allows you to place a wall near your space center and have those pesky Kerxicans pay for it. Seriously, there is. But i'm not here to talk about that.

Mods available include, but are not limited to: part sets with massive fuel tanks, engines and more; intricate, advanced space capsules for all your exploration needs; plugins that allow you to time your maneuvers, get better at docking or put things on autopilot; visual mods that give you enhanced skyboxes and magnificent atmospheres; whole new planets altogether that expand your frontiers greatly. And more. I could probably talk for hours about the various mods that are available, but I won't. I'll just say that most of them are amazing. If you're buying this game, make sure to grab a few mods. If you already have it, but don't use mods: Why?! If you have mods: Get some more mods. Mod it till it breaks, as some people would say.

There are plenty of things that I have omitted from this review - mostly because I want to end things here. I could probably talk about the magnificence of docking, the beauty of well-placed orbital maneuvers or other things that could make a NASA engineer smile gleefully. For now, though, i'll advise you to place yourself firmly into the capsule and go into space.

To summarize: Kerbal Space Program is an excellent space game that provides great experiences, combined with interesting gameplay and great mods, all while being a highly successfultake on sandbox, exploration and simulation alike. I can absolutely recommend it.
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3 of 3 people (100%) found this review helpful
725.5 hrs on record
Posted: October 7
Kerbal Space Program is truly something unique.

How do you market a game about rocket science -- the default analogy for "something extremely complicated" -- to an audience big enough to justify your budget? Well...there's a lot of little things that make it playable to many people.

First of all, it's a make-your-own-experience sandbox. Just like Minecraft (before there was an End), there's no final goal, no objective arrow. It's just you, an bunch of spaceship parts, a few kerbals, a custom solar system, the infinite expanse of space, and explosions. Lots and lots of explosions.

Second of all, this game about rocket science isn't about ALL of rocket science. There's quite a lot of liberty taken with the laws of physics, all in the name of simplicity. You don't have to worry about fuel flow, or life support, or the speed-of-light delay. All of that is benched in favor of less subtle things, like orbital mechanics, atmospheric shock-heating, and (look this up; it's practically KSP 101) delta-V and Tsiolkovsky rocket equation.

But here's the best part; all of these ignored facets of space travel can be added into the game. KSP has a very robust and active modding community, and I'm sure enough mods exist to make the game as realistic as you could possibly demand. Life support? There's a mod for that. Several, actually, in varying degrees of difficulty. Fuel flow? Part of Realism Overhaul. Speed-of-light delay? Check out RemoteTech. There are even mods that replace the stock solar system with our very own, real system, and even mods that add entirely new, dreamed-up systems. (I highly recommend starting out with no mods, then adding them as you become comfortable with what you already have.)

Really, Kerbal Space Program is great for the same reason Minecraft is great. It expects nothing in particular of you, it just wants you to do whatever comes to mind. If that means strapping a hundred boosters together as randomly as possible and watching the fireworks, that's fine. If that means methodically landing on every planet and moon one-by-one, that's fine. If that means brutally murdering your kerbals, well, heck, they're just as surprised to be alive as you are, so go for it.
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Recently Posted
BOT Derpic Potato
3.8 hrs
Posted: October 23
12/10 ign would crash again
Helpful? Yes No Funny
68.2 hrs
Posted: October 23
This is my first review of any game on Steam so, the short version is: BUY THIS GAME if you can because it is awesome and you'll have tons of hours of fun.

Now, for the long version...

Although I highly recommend this game, I must first start with the main negative aspects, which could make you refuse to buy it.

First of all, it is a highly scientific game, which will require of you hours and hours of watching youtube videos of other people explaining what is what in this game. The in-game tutorials aren't very helpful (at least for me), too short and barely scratch the surface. Luckily, the community is extraordinary and you will find a lot of help in many places. You will need to learn a lot of physics and other aerospace stuff to understand the game, which in its essence is cool but for many, a game is a reason to relax, not to learn complicated things. So, you will have to do a lot of research before you can play the game well. Its tutorials aren't going to help you very much.

Second, it is quite buggy even now, in 1.2. Especially if you use mods, it will crash to desktop a lot of times so save often. And even though it doesn't look much, the graphics require a good PC. But played stock, 4 GB of RAM are plenty.

Now, for the good part.

It is a hugely entertaining and educating game. You will learn a lot about how hard was it for the early pioneers of NASA to get a hang of launching stuff into space. Of course it is far from reality, but you will get a pretty good idea of it. At least, you'll get closer to it than with any other simulator. You will have to start from scratch, learning how to launch a rocket, how to build a plane, how to take into account the center of weight vs center of lift stuff, you will deploy sattelites built by your own hands (click by click), you will visit other worlds, plot courses that require enough celestial mechanics knowledge on your part. Your way of thinking will CHANGE.

If you are passionate about astronomy, this is your game. If you are passionate about astrophysics, this is your game. If you love building stuff, being patient enough to see them explode then rethink them, if you love learning thousands of things about planes and rockets, THIS IS YOUR GAME.

There are many detailed reviews about the game, here on Steam and elsewhere. The game is worth every penny so try saving some cash or just buy it, plain and simple. I've spent 60+ hours on Steam and at least 100 before that on another version of the game. I've barely scratched the surface. It keeps me up at night, making me plan for my next contraption and my next launch. So...

WARNING: It is highly addictive! At least, if you're into this kind of games. I uninstalled it and reinstalled it at least 10-15 times but I keep getting back to it. It is by far the most interesting, challenging and rewarding game (all together) I've played in my life.

Now... If this hasn't convinced you to buy it, just read the other reviews on this page. I'm just a newbie, but others have more comprehensive opinions about the game that will convince you this game is worth the money. I've got mine from ♥♥♥ at half the price but if I have had the money, I would've payed the full price or double. It's a lot of work inside a very beautiful game.


As a final note: 95/100. Hard to learn, very hard to master, fun to play and addictive to discover its secrets. BUY IT.
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826.5 hrs
Posted: October 22
played it for hundreds of hours
Helpful? Yes No Funny
344.9 hrs
Posted: October 22
Anyone who writes a bad review of Kerbal Space Program is just plain lying.
Helpful? Yes No Funny
21.7 hrs
Posted: October 22
Helpful? Yes No Funny
91.3 hrs
Posted: October 22
All I can say is WOW! I bought this when it first came out, played for short time, decided it was cool, but too hard, then forgot about it. Recently, I noticed that I had downloaded an update through Steam. I decided to boot it up again and I'm glad I did. I am having an absolute blast with the career mode and I really like all the mods that are out there. It makes it "your game". 3...2...1...AWESOME!
Helpful? Yes No Funny
1.1 hrs
Posted: October 22
very gooooooooD!!!
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a bag full of puppies
76.2 hrs
Posted: October 22
Helpful? Yes No Funny
167.9 hrs
Posted: October 22



Pick your superlative and it still doesnt do KSP justice. The options on hand, the freedom of choice, the sheer audacity of it and it has REAL and PROPER physics, not crappy 3rd party rubbish that doesnt work or "faux" effects.

If you like space in any way, or if you like just blowing stuffs up, this game is a MUST have.

Personal rating for KSP - 9.5 / 10

Its that good.
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547.5 hrs
Posted: October 22
I'm one of the many fans of KSP, and it's essentially the only game that I play. Success at the game requires a significant knowledge about rocketry and orbital mechanics, and the game does make it possible to learn quite a bit of what you need to know. There is also a lot of support in the community (for example, the interplanetary travel calculator that shows the orientation in orbit needed to reach other planets). I've put quite a few hours into KSP and still have plenty of challenges left. Making it safely to another celestial body (a planet or a moon) feels like a significant challenge - it's very satisfying.
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