Enter the wavelength of any wave in nanometers into the calculator to convert into Joules of energy. This calculator can also calculate the nanometers given joules.

Nanometers to Joules Formula

The following formula is used to convert a wavelength in nanometers to joules. 

E = h*c / (v/10^9)
  • Where E is the energy of the wave in Joules
  • h is the plank constant = 6.62606957×10^−34 J-s
  • c is the speed of light = 299,792,458 m/s
  • v is the wavelength in nanometers

To calculate Joules from nanometers, multiply the plank constant by the speed of light, then divide the result by the result of the wavelength divided by 10 to the 9th power.

How to convert nanometers to Joules?

Nanometers are a unit of length while Joules are units of energy. Therefore, there is no direct conversion that can happen through a factor such as when converting a length to another length unit.

If these are completely different units, then why are they even related? The reason that nanometers and Joules are mentioned together is that nanometers are common units used to describe wavelengths of waves, and waves are often analyzed for the amount of energy they have.

In order to convert the wavelength into Joules, you simply need to know the length of the wave, the plank constant, and the speed of light.

To calculate Joules from nanometers, multiply the speed of light by the plank constant and then divide by the wavelength in meters.

Example Problem

The following is an example problem on how to perform this conversion:

First, determine the speed of light and plank constant. These are both known universal values.

h = 6.62606957×10^−34 J-s

c = 299,792,458 m/s

Next, determine the wavelength in nanometers and then convert to meters. For this example, the wavelength is 400 nanometers. To convert into meters, divide by 10^9.

v = 400 / 10^9

v = 4^-7

Finally, use the formula above to calculate the Joules:

E = h*c / (v)

E = 6.62606957*10^-34 * 299,792,458 / 4^-7

E = 3.254 e^-21