Sandbox mode is one of the three available game modes in Kerbal Space Program. It is an alternative to the guided and resource-limited career mode and the technological advancement dependent science mode, one in which players may freely construct any rocket they can imagine without constraint. In exchange for total freedom, sandbox will not deliver rewards, register progress, or acknowledge anything the player does in general. It functions more as a playground than as a game.
Sandbox differs from career mode in a number of ways:
- All parts start out unlocked; nothing is required to gain access to them.
- Parts do not cost funds, and may be used in any quantity without limit.
- No restrictions are placed on the use of mod parts in vehicles.
- The science system and related parts do not function. Crew reports, EVA reports, and surface samples cannot be gathered. Attempting to observe experiments will not earn the player anything. However, it still displays the window. Also, the Research and Development Facility cannot be accessed.
- Mission Control cannot be accessed, and Contracts are disabled.
- The Administration Facility cannot be accessed, and there are no business strategies available in this game mode.
- The reputation system is disabled.