System security

A star system's Security Level is a rough measure of how hazardous is that particular system. Players also commonly use the terms Sec Level, System Sec, Security Rating, and Sec Rating. It is displayed in-game as a positive number with a single decimal place in the range [0.0, 1.0]. Security level should not be confused with Security Status, which is an attribute attached to a player character.

The security level of a player's current system is always displayed in the System Information display on the upper left of the screen, both in space and while docked.

System Security Classifications and Aggression

There are three general classifications of systems based upon system security: High Security, Low Security, and Null Security.

High Security

High Security systems are those with a security level of 0.5 to 1.0. Players also commonly use the terms High-sec, Highsec, Hi-sec, and Hisec.

In these systems, stargates may have a CONCORD, customs, and/or faction navy presence; stargates and stations will have sentry guns; and aggression (i.e. becoming subject to a Global Criminal Countdown) will provoke a response from CONCORD and any nearby sentry guns. Aggression resulting in the destruction of another player's ship and/or pod will result in a loss of security status. The higher the security level of the system, the more rapidly CONCORD will arrive to engage the offending player.

Low Security

Low Security systems are those with a security level of 0.1 to 0.4. Players also commonly use the terms Low-sec, Lo-sec, Lowsec, and Losec.

In these systems, stargates and stations will have sentry guns, and aggression (i.e. becoming subject to a Global Criminal Countdown) will provoke a response from any nearby sentry guns. Aggression resulting in the destruction of another player's ship and/or pod will result in a loss of security status.

Null Security

Null Security systems are those with a security level 0f 0.0. Players also commonly use the terms Null-sec, Nullsec, and 0.0 (pronounced "zero zero", "zero dot zero", or "oh dot oh").

These systems are essentially lawless and no NPC organizations will respond to aggression, nor will actions of any kind result in a loss of security status.

System Security-Limited Game Mechanics

Various game mechanics are affected or limited by system security. These include:

• Asteroid types found in asteroid belts. More lucrative asteroids are generally found in lower-security systems.
• General difficulty of rat spawns, including belt and gate rats. More difficult rats are generally found in lower-security systems.
• General difficulty of cosmic anomalies and cosmic signatures. More difficult sites are generally found in lower-security systems.
• Reward level of missions. Greater rewards for the same mission are given by agents in lower-security systems.
• True capital ships (i.e. ships that specifically require the Capital Ships skill) may not enter highsec systems.

Anchoring

The security level of a system may limit what may be anchored in that system.

• 0.9 - 1.0: No structures or containers may be anchored.
• 0.4 - 0.8: Containers may be anchored. Starbases and starbase structures may be anchored with sufficient standing, except for moon mining structures.
• 0.0 - 0.3: All containers and structures may be anchored, with no standing requirement.

Security Status

Players with a sufficiently low security status may invoke a faction navy response depending upon the security level of the system.

• 1.0: -2.0 and lower will be engaged by the faction navy
• 0.9: -2.5 and lower will be engaged by the faction navy
• 0.8: -3.0 and lower will be engaged by the faction navy
• 0.7: -3.5 and lower will be engaged by the faction navy
• 0.6: -4.0 and lower will be engaged by the faction navy
• 0.5: -4.5 and lower will be engaged by the faction navy

True Security

A given system's security level is actually a real number in the range [-1.0, 1.0]. This is known as the system's True Security Level, True-Sec, or Truesec. It is modified to the in-game displayed value by range and rounding rules:

• [-1.0, 0.0] = nullsec (always 0.0)
• (0.0, 0.05) = rounded up to lowsec (0.1 security level)
• [0.05, 0.45) = rounded half up (lowsec)
• [0.45, 1.0] = rounded half up (highsec)

A system's true security may be desirable to know because nullsec systems may have a truesec range from -1.0 up to 0.0 which continues to affect various game mechanics.

Legacy Rounding Glitch

In the past, truesec values in the range (0.0, 0.5) were rounded half up, i.e. rounded down to 0.0 because all numbers in that range are below 0.5. This was a bug, because EVE considers all systems above a trusec rating of 0.0 to be lowsec but the game displayed their security level as "0.0". This bug not only caused some confusion (there were sentry guns within apparently nullsec systems) but also some problems in the form of inadvertent security status loss in what seemed like nullsec.

This bug has been fixed, and the game now uses the rules above. This ensures that any system displayed as "0.0" is truly nullsec. Some third-party utilities may not know of the above rules, and so may incorrectly display a system's security level.