If you own one of the original Scalextric tracks of lucky ones, you can calculate that track length in real time because you get this app very interesting.
All you have to do is indicate the type of trunk and quantity used in its construction.
The name of the track is: Standard Stratified, Inner R1 Curve 90º and Standard Street Crossover.
Skeletal Track Length Calculator shows the length of the track on the matrix and imperial unit system. It also calculates the pieces that are used on the track and which are not missing.