An updated version of this guide is available at
Tutorial: Dimensions. This version is retained for archiving purposes.
Below is a list of important Half-Life dimensions. These should be taken as guidelines and are only applicable to standard Half-Life. Any mod that has changed the default physics may or may not abide by these guidelines.
Ground Obstacle Height
This is the maximum height, in units, an object can be while still allowing the player to walk over it.
Overhead Obstacle Height
This is the minimum distance, in units, that can be between the ground and an object while still allowing the player to pass underneath.
Minimum Path Width
This is the minimum width, in units, that can be between two objects while still allowing the player to pass between them.
Jump Height
This is the maximum height, in units, an object can be while still allowing the player to jump on top of it.
- crouched: 44
- walking: 44
- running crouch-jump: 62
Jump Span
This is the maximum distance, in units, that can be between two objects of the same heigh, while still allowing the player to jump from one object to the other.
- crouched: 99
- walking: 109
- running: 239
- running crouch-jump: 259
This article was originally published on the
Valve Editing Resource Collective (VERC).
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