Abstract: Measurement standards are optimized via the unification of measurement unit of physical properties into dimensionless numbers. There is an invariance equations governing natural phenomena, and <data> is never abstract and inevitably linked to <physical representation>. All measurement units (physical quantities) into dimensionless numbers with the minimum natural (boundary) condition are unified based on nature's invariance equations, setting up the new measurement standard and optimizing measurement and calculation. In the expression of physical quantities, numbers representing quantity and units are combined. Based on nature's invariance equations, the minimum object-based numbers related to all measurement units are discovered. Using these numbers, all measurement units including basic units can be converted into the system of dimensionless numbers. As all measurement units are expressed as numbers without any dimension, compatibility of measurement units is in place.