Experience (XP) is a unit of measurement used to quantify a Kerbal's progression throughout their missions. The Experience system works only in Career mode; in Sandbox and Science modes there are no restrictions on abilities, all kerbals are top level.
Experience is gained for completing a variety of achievements (described below), leading to higher levels in their specialization. Each kerbonaut specializes as either a Pilot, an Engineer, or a Scientist. Higher levels grant additional abilities, making veteran crew progressively more capable (up to a point).
Orbiting, planting flags, and escaping from the gravity of planets and moons grants various amounts of experience depending on the planet. Each Kerbal can only gain the experience once per celestial body, so planting multiple flags or repeatedly orbiting a planet do not provide any further experience for the same Kerbal. Additionally, experience from a given celestial body is only granted for the most valuable achievement and is not cumulative, so orbiting the Mun (3 XP) and planting a flag on it (5 XP) will only ever grant a total of 5 XP, not 8 or more (even if done on separate missions). The kerbonaut gains the experience and reaches a new level only upon returning to the Astronaut Complex by recovery or by using the Level Up Crew function of the Mobile Processing Lab.
- Note, since 1.2 a single flag planting grants the additional XP to all landed (or splashed down) kerbals within physics range.
- Note, the in-game summary for individuals shows rounded experience numbers, which can be confusing when displayed experience appears to be enough to achieve a level but the level is not granted.
|Order||Celestial body|| Fly by
| Plant flag
As Kerbals gain experience, they gain levels in their specialization. Kerbals start at level 0, and can reach level 5. The level of the kerbonaut represented by number of stars.
|Level||Stars||Additional XP||Total XP|
- Initial Release