Random Wavelength

A random wavelength from the visible spectrum (380 to 700 nm), converted to the exact spectral color your eyes would perceive.

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380 nm480540600700 nm

Hex

RGB

Freq

Energy

or press Space

Statistics

Gens

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Avg λ

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Violet End

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Red End

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Last

Average λ convergence toward 540 nm

Visible Light: A Narrow Window

The electromagnetic spectrum spans wavelengths from picometers (gamma rays) to kilometers (radio waves). Your eyes respond to an astonishingly narrow band: roughly 380 to 700 nanometers. Within that sliver sits every color humans have ever named. Each wavelength in this tool corresponds to a single pure spectral color, the kind produced by splitting sunlight through a glass prism.

Newton and the Prism

In 1666, Isaac Newton directed a beam of sunlight through a triangular glass prism and observed it fan out into a continuous band of colors: violet, blue, green, yellow, orange, red. Newton recognized that white light is a composite of all visible wavelengths superimposed. He coined the word spectrum for this rainbow display. The experiment demonstrated that color is a property of light itself, encoded in wavelength, rather than something added by the glass.

From Wavelength to Color

This tool uses Dan Bruton's spectral approximation algorithm to convert each wavelength to its closest RGB equivalent. Pure spectral colors occupy a narrow gamut that RGB monitors can only approximate: the vivid spectral green at 520 nm, for instance, is more saturated than any green your screen can physically produce. The algorithm maps each wavelength to piecewise linear RGB components and applies intensity falloff near the violet and red edges where human sensitivity diminishes.

Frequency and Energy

Wavelength, frequency, and photon energy are three perspectives on the same phenomenon. Higher frequency means shorter wavelength and more energy per photon. Violet light at 380 nm carries photons of 3.26 eV and oscillates at 789 THz. Red light at 700 nm carries 1.77 eV at 428 THz. The energy difference explains why ultraviolet light (just beyond violet) can cause sunburn while infrared (just beyond red) merely warms your skin.

Private by Architecture

Each wavelength is generated by crypto.getRandomValues() in your browser. The server delivers this page; your device selects the wavelength and computes the color. No data leaves your browser.