Version: 2018.1 (switch to 2018.2b or 2017.4)
  • C#
  • JS

Script language

Select your preferred scripting language. All code snippets will be displayed in this language.


Suggest a change


Thank you for helping us improve the quality of Unity Documentation. Although we cannot accept all submissions, we do read each suggested change from our users and will make updates where applicable.


Submission failed

For some reason your suggested change could not be submitted. Please <a>try again</a> in a few minutes. And thank you for taking the time to help us improve the quality of Unity Documentation.



public static var autoSimulation: bool;
public static bool autoSimulation;


Sets whether the physics should be simulated automatically or not.

By default, physics is updated every Time.fixedDeltaTime during the play mode. It happens automatically as part of the regular game loop.

However, there are cases where being able to advance physics manually is needed. One particular example simulating physics in the edit mode. Another example could be networked physics where rewinding time back and applying all the player input is required up on receiving data from the authoritative server.

To control the physics simulation manually, disable the automatic simulation first and then use Physics.Simulate to advance time. Note that MonoBehaviour.FixedUpdate will still be called at the rate defined by Time.fixedDeltaTime, but the physics simulation will no longer be advanced automatically.

See Also: Physics.Simulate.

Did you find this page useful? Please give it a rating: