Onside or offside?
Move the blue attacker and discover where the line is. Imagine this is the instant a teammate plays the ball.
Drag the blue player, use the slider, or press the arrow keys. Marker centres represent player positions in this simplified model.
Onside
The blue player has not passed the second-last defender, so is onside in this setup.
A position is only the first part
An offside position becomes an offence only if the player becomes involved in active play, such as playing the ball or interfering with an opponent.
Here, the ball stays behind the second-last defender and the goalkeeper is the last opponent. In a real match, the goalkeeper is not always the last opponent. Positions of the head, body and feet count; hands and arms do not.
No offside offence occurs when receiving the ball directly from a goal kick, throw-in or corner kick.
Explore IFAB Law 11