Freeze the pass, then find both references
Under IFAB Law 11, the ball matters as well as the second-last opponent. Position is judged when a teammate plays or touches it; the attacker must be nearer the goal line than both references to occupy an offside position. Involvement is a further question.
Imagine an attack travelling from left to right. A winger reaches a point six metres from the goal line. The intended receiver is eight metres from it, while the nearest relevant defenders are ten metres away. The receiver is beyond those defenders but still two metres farther from goal than the ball. That geometry does not put the receiver in an offside position.
Why the camera can mislead
A diagonal broadcast angle can make the receiver appear level with the winger even when their distances from the goal line differ. The useful comparison is along the length of the pitch, not the apparent gap between shirts on the screen. A ball travelling backwards is also only a clue: its direction does not replace the positional test at the touch.
Follow the passer’s contact frame first. Then compare the receiver with the ball and the opponent line in that frame. Watching only the moment of reception can turn a legal overlap into an apparent infringement because everyone has moved.
Questions answered
Does a backward pass guarantee no offside?
No. The receiver’s position at the teammate’s touch remains the starting point.
Does being beyond the defenders alone decide it?
No. The ball is an additional reference.
Sources & further reading
Official references for the subjects discussed. Service terms and device software can change.