To calculate **wavenumber** from wavelength, simply take the inverse of the wavelength. Ensure the wavelength is in centimeters, and the result will be in **cm⁻¹**, which is the standard unit for wavenumber.

The **Cm to Wavenumber Calculator** allows you to convert wavelengths (in cm or nm) to wavenumbers (cm⁻¹). This tool is particularly useful for applications in spectroscopy and physics, providing an easy way to switch between wavelength and wavenumber.

**Formula:**

$W = \frac{1}{\lambda}$

Where:

**W**= Wavenumber (in cm⁻¹)**λ**= Wavelength (in centimeters)

Variable | Description |
---|---|

W | Wavenumber (cm⁻¹) |

λ | Wavelength (in centimeters) |

**Example Calculation:**

Let’s assume you have a wavelength (**λ**) of **500 nm** (which is **500 × 10⁻⁷ cm**).

Using the formula:

$W = \frac{1}{500 \times 10^{-7}} = 2 \times 10^4 \, \text{cm}^{-1}$

So, the wavenumber is **20,000 cm⁻¹**.

Step | Calculation | Result |
---|---|---|

1 | Convert wavelength from nm to cm | $500 \times 10^{-7} = 5 \times 10^{-5} \, \text{cm}$ |

2 | Take the inverse of the wavelength | $\frac{1}{5 \times 10^{-5}} = 2 \times 10^4 \, \text{cm}^{-1}$ |