285/40 R23 doesn't belong to the most popular dimensions for tyres - there are tyre models available, which can be compared to
325/30 R21,
155/60 R15,
155/65 R13. Let's break down the sizing - 40 is height of the tyre, which is calculated as 40% of the tyre width (285mm), which means the sidewall height has 114 mm. The wheel diameter is R23, which means it fits to a 23 inch/584.2mm diameter wheel. The total circumference of the tyre is mm, which is very similar to 165/70 R13
(1763.06 mm), 245/50 R19
(2285.82 mm), 175/65 R13
(1752.07 mm), 255/30 R19
(1996.8 mm), 180/60 R17
(2035.12 mm), 255/40 R20
(2236.81 mm), 185/60 R16
(1974.18 mm).