Enter the final and initial energy states into the calculator to determine the change in energy; this calculator can also evaluate any of the variables given the others are known.

## Delta E Formula

The following formula is used to calculate the change in energy (ΔE) in a system:

ΔE = E_final - E_initial

Variables:

- ΔE is the change in energy
- E_final is the final energy state
- E_initial is the initial energy state

To calculate the change in energy, subtract the initial energy state from the final energy state.

## What is a Delta E?

Delta E is a metric used in colorimetry to quantify the difference between two colors. It is a single number that represents the ‘distance’ between two colors in a multi-dimensional color space. The term ‘Delta’ is used to denote difference, and ‘E’ stands for Empfindung, a German word for sensation. The calculation of Delta E takes into account the differences in the three attributes that define a color: hue, saturation, and lightness. A Delta E value of 0 would mean the two colors are identical, while a higher value indicates a greater difference between the two colors. The exact interpretation of a specific Delta E value can depend on the application and the specific color space being used. For example, in some contexts, a Delta E of 1.0 is often considered the smallest color difference that can be perceived by the human eye.

## How to Calculate Delta E?

The following steps outline how to calculate the Delta E:

- First, determine the initial color values (Lab or RGB) of the reference color.
- Next, determine the initial color values (Lab or RGB) of the sample color.
- Next, calculate the differences between the initial color values of the reference color and the sample color.
- Finally, use the differences to calculate the Delta E value using the appropriate formula.
- After inserting the values and calculating the result, check your answer with a Delta E calculator.

**Example Problem:**

Use the following variables as an example problem to test your knowledge.

Initial color values of the reference color: L = 50, a = 20, b = 10

Initial color values of the sample color: L = 45, a = 18, b = 12