Kerbal Space Program is a multi-genre game where players create their own space program.
User reviews: Overwhelmingly Positive (18,036 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, 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.


225 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.

196 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
136 of 144 people (94%) found this review helpful
4 people found this review funny
51.8 hrs on record
Posted: February 10
Early Access Review
✓ Fun, realistic rocket simulation
✓ Three different modes: sandbox, science, and career
✓ Huge variety of things to do, from exploring Kerbin to launching complex space stations

✘ Are there really any cons to this game?
Was this review helpful? Yes No Funny
152 of 173 people (88%) found this review helpful
70 people found this review funny
94.1 hrs on record
Posted: February 7
Early Access Review
Day 1: Made Kim Jong-Un proud.
Day2: Made NASA proud.

Was this review helpful? Yes No Funny
78 of 80 people (98%) found this review helpful
2 people found this review funny
63.0 hrs on record
Posted: February 22
Early Access Review
It's not exactly rocket science is it?....oh wait, yes it is.

Kerbal Space Program is a game about building spacecraft and, unless you're very good at the game, watching them blow up which is currently in Early Access. In KSP you design and build your very own spacecraft/rockets and spaceplanes which you then use as you leave Kerbin to further the scientific knowledge of the humble kerbal. With a vast array of parts at your disposable it's daunting at first, well it's daunting for a while, but once you get the hang of it this game is a blast, especially if you have any interest in astrophysics or aerospace engineering.

KSP has four different game modes each of which I will give a brief description of.

First off there's sandbox mode. In sandbox mode you have no limitations and most importantly you have access to all of the parts right away, this is the perfect way for new players to get to grips with building and figuring out what works well and how the game works.

Next we have scientific mode. In scientific mode you have to generate science points from doing experiments in different places, e.g. the surface of Kerbin or low Kerbin orbit. Science points you earn can then be spent on new technologies in the tech tree which unlock new parts which help you to go to new places to complete more experiments. You begin with few parts which are basic so unlocking new technologies in imperative to progress.

Up next is career mode. Career mode is scientific mode but now with money and reputation to worry about. Money is earned by completing contracts, such as putting a part on your rocket and getting it to a certain altitude and then money is spent on parts for your rocket or spaceplane. Reputation is earned by successfully completing contracts, the higher your reputation is the better the contracts you get offered are. However, reputation can be lost through either failing contracts or losing kerbals.

Last, and probably least depending on what you like, are the game's pre-made scenarios. Ranging from tutorials on docking to the NASA redirect mission this game mode is what you would expect it to be, just different scenarios to try out, not much to say about this one.

+Graphics are pretty nice
+Lots of different parts
+The building menus are good and building is relatively easy, by easy I mean straightforward to use not easy to make decent vehicles
+A number of different planets and moons, each with different appearances and properties
+Good controls and useful hotkeys
+Good staging setup
+Endless possibilities of what you can make, from simple little rockets to huge spacestations in orbit around distant planets
+Reasonaly good physics but not perfect (I'll get to that later)
+Plentiful explosions
+Huge replayability
+Great modding community and adding mods is extremely easy
+Kerbals are nice little race and you can get attached to the more well known kerbals quite easily (I <3 Jeb)

+/-Very basic tutorials, this game really throws you in at the deep end

-Immensely steep learning curve, I'm 60+ hours in and I've only recently made it to the Mun (and successfully landed)
-The physics and controls for spaceplanes are pretty bad, spaceplanes have clearly been neglected in favour of rockets


An outstandingly good vehicle builder/sandbox game which is perfect for anyone with an interest in space, the related physcis or anyone who likes building vehicles.

El K.
Was this review helpful? Yes No Funny
72 of 74 people (97%) found this review helpful
51 people found this review funny
394.7 hrs on record
Posted: February 26
Early Access Review
1st hour playing: WHAT DO I DO WHY IS IT BLOWING UP
400th hour playing: If my calculations serve me right with this T/W ratio It will take me 1 minute 43 seconds to burn at my periapsis to reach duna insertion at which point I will get into an eliptical equatoral orbit and perform an aerobrake at 16km to get into a steady circular orbit and then I will descend with one of my 4 spaceplanes I took to go to the north pole at which I will set up base at my already existing rover while getting TAC resources to monitor life support and make sure my colony of 212 kerbals can live.


Edit because for some reason this gained popularity, proper review:

Endless fun, so much to do. Bored of building rockets? Build a space plane! Fed up of the mun? Go to Duna! Don't want to leave the atmosphere? Build whatever you want! The list goes on!

Fantastic modding community and fantastic mods. So much more expansion on an already amazing game.

Fantastic community in general, some of the nicest people I've met have came from this game. They are such a helpful bunch and I'm glad I'm with them! They'll most likely love to help you. There's also a bunch of fantastic YouTubers such as Scott Manley and others... (too many to name) :)

YOU CAN LEARN STUFF FROM THIS AND GAIN NEW INTERESTS! Before I played this I had no interest in space or space exploration whatsoever but now I actively follow space news and am quite knowledgable on the subject. I have also learnt a fantastic deal of orbital mechanics just from playing and learning the game.


The engine and optimisation. This game uses Unity and it only uses 1 CPU core. This can be a major problem if running a multicore with low clock speed. The 32bit version of the game is a whole lot more stable but limits your RAM meaning that if you have a ton of mods you can run into a lot of crashes but thankfully there are mods out there such as ATM (Active Texture Management) and texture replacer to limit the amount of RAM the game uses. 64bit as of now is still pretty unstable with mods.

The learning curve and tutorials. The learning curve on this game is huge, I'm not complaining much about this one as rocket science isn't exactly easy is it? You can learn from trial and error and it's how I learnt alot but some things you just have to read up about or watch a tutorial on youtube. There isn't really much of a tutorial in game either.

Conclusion: Buy it. It's really fantastic.
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99 of 114 people (87%) found this review helpful
38 people found this review funny
1,291.1 hrs on record
Posted: February 6
Early Access Review
Finally figured out how to get into orbit. 10/10
Was this review helpful? Yes No Funny
43 of 50 people (86%) found this review helpful
28 people found this review funny
159.9 hrs on record
Posted: February 24
Early Access Review
>put a seat on top of a rocket
>put bob in the seat
>crash into the ground
>bob survives

11/10 would recommend
NASA certified physics
Was this review helpful? Yes No Funny
37 of 41 people (90%) found this review helpful
2 people found this review funny
86.6 hrs on record
Posted: February 4
Early Access Review
I can honestly say that had this been in existence when I was younger [turned 42 today] I would have been able to fullfil my dream of being in space. I know, sounds corny I'm sure but this app and it's game play takes me back to my youth where Astronomy and Space were most of what I could dream, think and talk about.

Roll ahead a few decades and this game gives me such a sense of freedom, accomplishment and challenge. Sure it's geeky, nerd stuff but honestly what isn't these days? Madden 2015? Sure, geeks playing pixels of sports greats they can never be like so I guess it's not far off. (lol)

This 'game' as they call it will teach you things about the science, mathematics and common sense problem solving that could help you in your life. I'm sure by this point you're saying 'But how will an orbit trajectory to Mun help me..?' and 'How is knowing the dV to escape the SOI of Kerbal going to help me..?' and you for one would be right. These, while still teaching the literal effect in game, also teaches you about solving sometimes complex puzzles or math problems or those 'how could I even do that?' types of questions. From the first launch, which in itself is not 'easy' by any stretch of the imagination; to the 100th, 200th and several thousandth launch later you want to do more and push further into space. It's those types of feelings that mold and lead those younger generations to wanting and wishing they knew and could do more.

Much like an aging dreamer, who at his younger years had always dreamt of getting the chance to leave this floating rock we call home.

Game is great. You just have to dream a little more, want a little more and do a little more.

TL:DR - Game is stupendous and anyone interested in space, space flight and rocketry with a keen sense of having fun all the while doing math, physics and all that wonderful science stuff without really knowing you are/can/will.

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67 of 91 people (74%) found this review helpful
81 people found this review funny
1,259.2 hrs on record
Posted: February 11
Early Access Review
It's some kind of third person FTL but I haven't played it a lot tbh.
Was this review helpful? Yes No Funny
36 of 43 people (84%) found this review helpful
20 people found this review funny
411.7 hrs on record
Posted: February 18
Early Access Review
10/10 -ign its like skyrim but with rockets
Was this review helpful? Yes No Funny
42 of 56 people (75%) found this review helpful
5 people found this review funny
49.5 hrs on record
Posted: February 3
Early Access Review
You need this.
Was this review helpful? Yes No Funny
21 of 22 people (95%) found this review helpful
1 person found this review funny
187.8 hrs on record
Posted: February 14
Early Access Review
This game is about extreme pre-planning, organisation, attention to details, patience, creativity and a mental breakdown.

This is the Rocket Science!

Was this review helpful? Yes No Funny
16 of 17 people (94%) found this review helpful
1 person found this review funny
17.7 hrs on record
Posted: February 17
Early Access Review
I put off Buying this "game" (Its so educational!) for months and months........

What was i thinking!?!?

Years of fun to be had! Steep learning curve, but totally worth it!
Not many games are as "Overwhemingly Positive" as this - and with good reason.

If your interested in Space / Rockets / Engineering or if you just fancy a challenge (Or blowing stuff up!!) Its a must buy!

I owe the countless Kerbals ive sent to their deaths a 10/10.
Was this review helpful? Yes No Funny
15 of 16 people (94%) found this review helpful
2 people found this review funny
118.8 hrs on record
Posted: February 14
Early Access Review
Even though still in Beta, a great game with mods more enjoyable than fuitcake. Definately would recommend to all.
Was this review helpful? Yes No Funny
10 of 11 people (91%) found this review helpful
2 people found this review funny
95.2 hrs on record
Posted: February 17
Early Access Review
I'm going to keep this somewhat short and sweet

At the time of writing, Kerbal space program is in beta and there is talk of how soon it will be until it emerges from beta. But since its release in July 2011, it grown to become an outstanding example of Enthusiasm, Humor, and Profound triamph in a game. No matter whether your accomplishing great feats of exploration and scientific achievement......Or maybe you watched your beloved ship erupt into flames and debris becuase of a fatally unseen flaw. There is always something spectacular to be seen (Like your blown-up ship) or something to have a laugh at (Again like your blown-up ship)

My recommendation?

Buy this game, do something great, do something ridiculous, mod it, find something else just as great and just as crazy to do. My little tip is that i get emotionally attatched to some of my kerbals (Especially Jebediah). There's so much fun to be had and tenderness to experience. There's no reason not to buy this game and experience it. So do it!!!
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10 of 11 people (91%) found this review helpful
314.4 hrs on record
Posted: February 17
Early Access Review
Imagine, if you will, any alien race on another planet. Image them looking up at the stars and trying to reach them. We went through our own space program in the 60s, and we got a taste of what it means to leave your own gravity well. Well, certainly we can't be the only species trying to do this. Playing Kerbal Space Program makes me feel connected to every other species attempting to leave their home planet. It's not just us on Earth, but everywhere. KSP makes me feel like I have NASA in my backyard and can throw together a rocket and try it out whenever I like. I recommend this game for young and old alike. If you like rockets because they're cool or because you remember Neil saying those memorable words, please play this game!
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12 of 15 people (80%) found this review helpful
2 people found this review funny
4.1 hrs on record
Posted: February 9
Early Access Review
"It's not homocide, It's ROCKET SCIENCE!" -Anonymous

10/10 would kill kerbals again.
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7 of 8 people (88%) found this review helpful
649.9 hrs on record
Posted: February 24
Early Access Review
Thought about Space and stuff, bought this game.

Learn a lot of actual things like orbital mechanism.

Build rockets and shoot for the stars (Moons).


Hous Well-Spent.
(Hmm where is the exit?)
Was this review helpful? Yes No Funny
7 of 9 people (78%) found this review helpful
2 people found this review funny
190.3 hrs on record
Posted: February 8
Early Access Review
<clarkson> Welcome to the best sandbox the world </clarkson>

You put your little green men in an airtight capsule. You strap the capsule to a giant explosive device. You launch said device into the face of GOD HIMSELF at incredible speeds. Enough said? The stock game is excellent and hours of fun, and the modding community is very active. Endless possibilities.

The only downside is sometimes heavy modding causes instability. Backup your save files and be prepared to reinstall if you use a lot of mods, especially experimental ones.

Do: read a tutorial
Do not: expect success
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3 of 4 people (75%) found this review helpful
1 person found this review funny
252.4 hrs on record
Posted: February 7
Early Access Review
Quite the revolutionary game if you ask me. Not only do you get to build your own rockets, spaceplanes, and whatever else you can think of. You can also build your own learning curve as well! With the help of modifications that make the base game even easier or more difficult!

Cannot get to the mun? Get a mod that can change engine specific impulse so you can travel further!

Planted a flag on every planet and moon? Get a mod that makes the Kerbol system resemble ours on a 1:1 scale!

Game crashing because of too many mods? There is a mod to fix that!

Once you have mastered KSP in all it's glory there is still fun to be had. Especially because there are many things to master in the base game like: docking, spaceplanes, and of course not running out of fuel before reaching your destination so you can return to Kerbin. The community, and modmakers only make the game even more in depth and fun!

You don't like modding your game? Kudos to you vanilla extremist, I still haven't even done everything in stock KSP yet. Just goes to show how much fun you can have in this game with plenty of things to do! Well worth it's price!

10/10 Still haven't touched the spaceplane hangar
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1 of 1 people (100%) found this review helpful
181.4 hrs on record
Posted: February 22
Early Access Review
A great land/air/space-craft building game with nice system for building the crafts, a pretty decent physics engine and a beautiful planetary system. Even better, I find, is the game's incredible modding community as there are pages upon pages of cool and interesting mods to make the game that much more....interesting!
A definite 10/10.
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