How can u tell the diffrence of isotonic and hypertonic

An isotonic solution requires the same osmotic pressure as the solution to which it is compared.  For example in an isotonic saline solution the concentration of sodium chloride is such that it requires the same osmotic pressure as human blood. If comparing two solutions with the same components, this means that the concentration of solute is equal in both solutions.

A hypertonic solution requires a higher osmotic pressure than the solution to which it is compared. If comparing two solutions with the same components, this means that the concentration of solute is higher than that of the other solution.