Is Kerbal Space Program co-op?

Not natively. Kerbal Space Program ships single-player; the community mod Luna Multiplayer (LMP) adds co-op — A shared space program with time-warp syncing. DMP is the older alternative.

Does Kerbal Space Program have PvP?

Only with the Luna Multiplayer (LMP) mod, which is co-op only.

Do we both need to own Kerbal Space Program to play together?

Yes. Kerbal Space Program is played online, so each player needs their own copy on their own Steam account (or PC Game Pass where it is offered). Steam Families can share a library, but two people cannot play the same shared game at the same time.

How many people play Kerbal Space Program?

About 1,844 players were in-game when this page's data was last refreshed (2026-09-09).

Ready Up — what game do we play?Compare two Steam libraries →

Multiplayer games › Sandbox & building › Space sandbox

Is Kerbal Space Program multiplayer? Yes — with Luna Multiplayer (LMP)

Not out of the box — but the Luna Multiplayer (LMP) mod makes it co-op. Kerbal Space Program is a space sandbox game released in 2015, 95% positive on Steam (127,162 reviews), with 1,844 playing right now. $39.99 on Steam.

Co-opSingle-player tooMultiplayer via mod: Luna Multiplayer (LMP)Sandbox & building · Space sandbox

How to play Kerbal Space Program with a friend: Luna Multiplayer (LMP)

A shared space program with time-warp syncing. DMP is the older alternative. Steam lists Kerbal Space Program as single-player, so it won't show up in Steam's own "games we both own" view as something you can play together — Ready Up counts it anyway, marked "Via mod", and you can hide mod-only games with one filter if that's not your thing.

Players: servers (small groups)
Modes: co-op
Status: Maintained — works with the current game version and gets updates
You need: KSP 1 only; a hosted server, or one player runs it
Price: Free

Get Luna Multiplayer (LMP) Or: DMP All 77 games with multiplayer mods →

In Kerbal Space Program, take charge of the space program for the alien race known as the Kerbals. You have access to an array of parts to assemble…

How Kerbal Space Program plays with friends, according to Steam

Online co-op: Not listed on Steam
Local / split-screen co-op: Not listed on Steam
Online PvP: Not listed on Steam
LAN play: Not listed on Steam
Single-player mode: Yes
Controller: Partial controller support
Mods: Steam Workshop

Steam's own category list for the game, as of 2026-09-09. "Not listed" means the store page does not claim that mode; community mods or Remote Play can still add it.

Steam tags: Space, Simulation, Sandbox, Physics, Science, Space Sim, Building, Moddable

Do you and a friend both own Kerbal Space Program?

Ready Up compares two Steam libraries and shows every multiplayer game you both have — including whether Kerbal Space Program is one of them — then helps you pick tonight's game with a weighted roll or a bracket.

Or open the Steam store page.

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Star Sonata 2

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Istrolid

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Galactic Junk League

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Tired of Kerbal Space Program? The Swap tab finds the closest unowned games of the same type that are newer or rated higher.

Quick answers

Is Kerbal Space Program co-op?: Not natively. Kerbal Space Program ships single-player; the community mod Luna Multiplayer (LMP) adds co-op — A shared space program with time-warp syncing. DMP is the older alternative.
Does Kerbal Space Program have PvP?: Only with the Luna Multiplayer (LMP) mod, which is co-op only.
Do we both need to own Kerbal Space Program to play together?: Yes. Kerbal Space Program is played online, so each player needs their own copy on their own Steam account (or PC Game Pass where it is offered). Steam Families can share a library, but two people cannot play the same shared game at the same time.
How many people play Kerbal Space Program?: About 1,844 players were in-game when this page's data was last refreshed (2026-09-09).

Ready Up is a free tool: enter two Steam usernames and it lists the multiplayer games you both own, runs a bracket to pick one, and suggests new co-op games that fit how you both play. Ratings, tags and player counts from Steam and SteamSpy; page updated 2026-09-23. Powered by Steam — not affiliated with or endorsed by Valve Corporation or Microsoft. Ready Up is a Somebody Decide program. How the data works · Legal & privacy · All types · Game Pass