The current legal limit is 1.6mm tread over the central 3/4 of the tyre in a continuous band, around the entire circumference of the tyre. RoSPA recommends tyre replacement at 3mm - your tyre is approximately 78% worn.
Using our diagram below we can demonstrate that a tyre has a unique code printed onto the outer surface, mainly made up of 3 sets of numbers.
The tyre width in millimetres. This is the part of the tyre that contains the tread.
The profile is the height of the Tyre sidewall as a percentage % of the tyre width. E.G: Sports tyres tend to have a low profile, giving more traction to the vehicle.
The diameter of the inner rim in inches. Generally medium sized family cars have sizes between 14" and 16".