Free Space Sim Games on Steam
Steam currently has 1,174 Space Sim games available to download and play. Explore our list of the best free games ranked by popularity and ratings. Data for this list is calculated from reviews and player counts reported directly by Steam and will be updated in real-time. Free Space Sim game rankings were last updated on 5/5/2025.
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- Best space sim games on Steam
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1. Galaxy Idle Clicker
Embark on an interstellar journey with Galaxy Idle Clicker! Conquer galaxies, upgrade your spaceship, and face off against a myriad of enemy ships. With engaging minigames, powerful upgrades, GIC delivers an unparalleled idle space adventure. Join the cosmic conquest today and dominate the universe!
Galaxy Idle Clicker holds the #1 spot for "best free Space Sim game on Steam" with a Player Score of 72. Its score was calculated by analyzing a total of 635 reviews on Steam. This breaks down to a total of 481 positive reviews and 154 negative reviews — making it "Mostly Positive" on Steam.
It can be played and ran on Windows systems. At the moment, it is possible to play Galaxy Idle Clicker on the Steam Deck (though some functionality may be limited).
2. Naval Action
Or were you deaf or were you blind when you left your two fine legs behind, Or was it sailing on the sea when you got the cannonball to your knee, I too was young and I was slim and I had a leg for every limb, But now I’ve got no legs at all, they were both shot away by a cannonball.
Naval Action has achieved a Player Score of 55, placing it in the #2 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 13,340 reviews on Steam. This breaks down to a total of 7,357 positive reviews and 5,983 negative reviews — making it "Mixed" on Steam.
It can be played and ran on Windows systems. At the moment, it is not possible to play or run Naval Action on the Steam Deck.
| Release Date | 6/13/2019 |
| Franchise | Game Labs, Inc |
| Developers | |
| Publishers | |
| Steam App Id | 311310 |
3. Idle Sphere
Stunning sphere-themed idle/incremental game. Experience simplicity's beauty.
Idle Sphere has achieved a Player Score of 54, placing it in the #3 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 244 reviews on Steam. This breaks down to a total of 135 positive reviews and 109 negative reviews — making it "Mixed" on Steam.
It can be played and ran on both Windows and Mac systems. At the moment, it is not possible to play or run Idle Sphere on the Steam Deck.
| Release Date | 11/17/2024 |
| Developers | |
| Publisher | Idle System, Inc. |
| Steam App Id | 3217600 |
4. Infinite Lagrange
Different forces strive to make their own way in the space and desire the control of the Lagrange system- a gigantic transportation network. You, emerging as one of the force leaders, find yourself in a time of challenges and opportunities.
Infinite Lagrange has achieved a Player Score of 55, placing it in the #4 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 878 reviews on Steam. This breaks down to a total of 494 positive reviews and 384 negative reviews — making it "Mixed" on Steam.
It can be played and ran on Windows systems. At the moment, it is not possible to play or run Infinite Lagrange on the Steam Deck.
| Release Date | 10/8/2021 |
| Developer | NetEase Games |
| Publisher | NetEase Games |
| Steam App Id | 1755920 |
5. Nova: Space Armada
An exceptional sci-fi strategy game based on space adventure as its core.
Nova: Space Armada has achieved a Player Score of 51, placing it in the #5 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 88 reviews on Steam. This breaks down to a total of 45 positive reviews and 43 negative reviews — making it "Mixed" on Steam.
It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.
| Release Date | 10/22/2024 |
| Developer | STONE3 PTE. LTD. |
| Publisher | STONE3 PTE. LTD. |
| Steam App Id | 1108270 |
6. Endless Sky
Endless Sky is a 2D space trading and combat game inspired by the classic Escape Velocity series. Work your way up from a relatively wimpy shuttle, cargo ship, or fighter, to a highly upgraded and customized flagship or to a massive fleet of warships or freighters.
Endless Sky has achieved a Player Score of 89, placing it in the #6 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 6,611 reviews on Steam. This breaks down to a total of 6,103 positive reviews and 508 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play Endless Sky on the Steam Deck (though some functionality may be limited).
| Release Date | 10/30/2015 |
| Developer | Michael Zahniser |
| Publisher | Michael Zahniser |
| Steam App Id | 404410 |
7. Star Conflict
Star Conflict is an action-packed, massively multiplayer space simulation game that puts players in the role of elite pilots engaging in a widespread interplanetary skirmish. The whole world for PVP and PVE!
Star Conflict has achieved a Player Score of 72, placing it in the #7 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 14,829 reviews on Steam. This breaks down to a total of 10,873 positive reviews and 3,956 negative reviews — making it "Mostly Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play Star Conflict on the Steam Deck (though some functionality may be limited).
| Release Date | 2/27/2013 |
| Franchise | Gaijin Network Ltd |
| Developer | Star Gem Inc. |
| Publishers | |
| Steam App Id | 212070 |
8. Starborne: Frontiers
Starborne: Frontiers is a free-to-play tactical autobattler with hundreds of unique ships. Form your fleet, customize it with a variety of equipment, and use strategy to create the perfect battlefield formation. Take on bounties, engage in the PvP arena, and bring order to the Frontier.
Starborne: Frontiers has achieved a Player Score of 64, placing it in the #8 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 240 reviews on Steam. This breaks down to a total of 163 positive reviews and 77 negative reviews — making it "Mixed" on Steam.
It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.
| Release Date | 10/14/2024 |
| Developer | Solid Clouds hf. |
| Publisher | Solid Clouds hf. |
| Steam App Id | 3021540 |
9. Nova Empire
Build up a Space Empire and establish control of the Galaxy and the Universe! Nova Empire is a multiplayer space game in which the aim is to build your empire and conquer the galaxy in epic space battles against your rivals with other allies worldwide!
Nova Empire has achieved a Player Score of 54, placing it in the #9 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 248 reviews on Steam. This breaks down to a total of 135 positive reviews and 113 negative reviews — making it "Mixed" on Steam.
It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.
| Release Date | 5/26/2022 |
| Developer | Gamebear Tech |
| Publisher | Gamebear Tech |
| Steam App Id | 1962770 |
10. X3: Farnham's Legacy
X3: Farnham's Legacy is a new game in the X3 space game series. TRADE, FIGHT, BUILD, THINK in a living and breathing universe, which incorporates a new storyline and yet more additions to the open, free-form gameplay that forms the core of all X series games.
X3: Farnham's Legacy has achieved a Player Score of 82, placing it in the #10 spot for the best free Space Sim games. Its score was calculated by analyzing a total of 597 reviews on Steam. This breaks down to a total of 519 positive reviews and 78 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on both Windows and Linux systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.
More Free Space Sim Games
Explore even more rankings for the 100 best free Space Sim games available on Steam.
| Image | Name | Actions | ||||
|---|---|---|---|---|---|---|
| 1,263 | 7/18/2024 | 72 | Free | Steam Charts | |
| 240 | 6/13/2019 | 55 | Free | Steam Charts | |
| 185 | 11/17/2024 | 54 | Free | Steam Charts | |
| 145 | 10/8/2021 | 55 | Free | Steam Charts | |
| 135 | 10/22/2024 | 51 | Free | Steam Charts | |
| 88 | 10/30/2015 | 89 | Free | Steam Charts | |
| 64 | 2/27/2013 | 72 | Free | Steam Charts | |
| 64 | 10/14/2024 | 64 | Free | Steam Charts | |
| 52 | 5/26/2022 | 54 | Free | Steam Charts | |
| 34 | 5/4/2021 | 82 | Free | Steam Charts | |
 | 30 | 9/22/2020 | 61 | Free | Steam Charts | |
 | 26 | 9/2/2024 | 57 | Free | Steam Charts | |
 | 25 | 9/25/2024 | 75 | Free | Steam Charts | |
 | 25 | 4/20/2022 | 72 | Free | Steam Charts | |
 | 23 | 2/11/2024 | 84 | Free | Steam Charts | |
 | 16 | 6/12/2020 | 63 | Free | Steam Charts | |
 | 12 | 2/12/2024 | 83 | Free | Steam Charts | |
 | 10 | 11/4/2020 | 65 | Free | Steam Charts | |
 | 8 | 2/24/2023 | 52 | Free | Steam Charts | |
 | 8 | 5/22/2024 | 87 | Free | Steam Charts |
Soures & References
Steambase has best-in-class data powered directly by Steam, our data partners, and in-house experts. Player counts and rankings are enriched, analyzed, and updated in real-time to ensure we surface the most up-to-date insights. Learn more about the Steambase approach to data collection and our review methodology.
- Valve Corporation. (2025, May 5). Steam Store. Steam Store.
- Valve Corporation. (2025, May 5). Galaxy Idle Clicker on Steam. Steam Store.
- Valve Corporation. (2025, May 6). Naval Action on Steam. Steam Store.
- Valve Corporation. (2025, May 4). Idle Sphere on Steam. Steam Store.
- Valve Corporation. (2025, May 1). Infinite Lagrange on Steam. Steam Store.
- Valve Corporation. (2025, May 6). Nova: Space Armada on Steam. Steam Store.
- Valve Corporation. (2025, March 24). Endless Sky on Steam. Steam Store.
- Valve Corporation. (2025, May 1). Star Conflict on Steam. Steam Store.
- Valve Corporation. (2025, May 6). Starborne: Frontiers on Steam. Steam Store.
- Valve Corporation. (2025, April 14). Nova Empire on Steam. Steam Store.
- Valve Corporation. (2025, March 13). X3: Farnham's Legacy on Steam. Steam Store.