Best answer by Bumblebee
Most meters do say Day/Night rate, in this case if you don't have that, compare the numbers to your previous online/paper bill, it will show you which rate is which and then compare the numbers,
As a general rule of thumb the lowest row of numbers are night rate and highest are day rate (As there are less night rate hours)
Be sure to compare with an old bill tho!
Updated 05/07/19 there's another topic on this here.
Have a great weekend,