Move along the visible spectrum to see each wavelength’s frequency, photon energy and approximate screen colour. Collect wavelengths into a palette you can edit, preview and export.
Loading the spectral data…
Spectral samples
Every sample in the chosen range, in wavelength order. The 380–700 nm range has 65 samples at 5 nm steps and 321 at 1 nm steps. These are points sampled from the spectrum, not every colour people can see.
Starter palettes
Spectral sample palettes hold the approximate screen colours of single wavelengths. Spectrum-inspired palettes are design colours made from those samples (pastel, muted or deep). They are kept apart because they are not colours of light.
Full Spectrum Study
Spectral samples
Seven samples 50 nm apart across the 400–700 nm teaching range.
400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm
Prism Seven
Spectral samples
The seven representative wavelengths used for the named teaching overlay, violet to red. White light has every wavelength in between, not just these seven.
410 nm, 440 nm, 470 nm, 530 nm, 580 nm, 610 nm, 660 nm
Violet–Blue Study
Spectral samples
The short-wavelength end, 400–480 nm in 20 nm steps.
400 nm, 420 nm, 440 nm, 460 nm, 480 nm
Cyan–Green Study
Spectral samples
Where blue turns to green, 485–545 nm in 15 nm steps.
485 nm, 500 nm, 515 nm, 530 nm, 545 nm
Yellow–Red Study
Spectral samples
The long-wavelength side, 570–650 nm in 20 nm steps.
570 nm, 590 nm, 610 nm, 630 nm, 650 nm
Warm Spectrum
Spectral samples
Yellow, orange and red samples from 575 to 675 nm.
575 nm, 595 nm, 615 nm, 635 nm, 655 nm, 675 nm
Cool Spectrum
Spectral samples
Violet, blue, cyan and green samples from 420 to 520 nm.
420 nm, 445 nm, 470 nm, 495 nm, 520 nm
Blue, Green and Red Regions
Spectral samples
One sample from each of the blue, green and red regions. Use it as the three-wavelength input in the prism lab.
450 nm, 530 nm, 620 nm
Narrow Green Band
Spectral samples
Five samples only 3 nm apart. Several share almost the same screen colour, which is why every 1 nm step is not visibly different.
525 nm, 528 nm, 531 nm, 534 nm, 537 nm
Pastel Spectrum Inspired
Spectrum-inspired (not spectral)
Pastel design colours made from five spectral samples. They are creative variations, not colours of light.
420 nm, 470 nm, 530 nm, 580 nm, 620 nm
Muted Spectrum Inspired
Spectrum-inspired (not spectral)
Soft, greyed design colours made from spectral samples, for calm interfaces and rooms.
440 nm, 500 nm, 560 nm, 600 nm, 640 nm
Deep Spectrum Inspired
Spectrum-inspired (not spectral)
Deep, dark design colours made from spectral samples, for strong accents and dark themes.
410 nm, 470 nm, 530 nm, 590 nm, 650 nm
Try it
Compare 450 nm and 650 nm
Put a blue and a red wavelength side by side and compare their frequencies and the spacing of their waves.
Which carries more energy per photon?
Is a photon of 450 nm light or of 650 nm light more energetic?
Collect five samples
Take five wavelengths spread evenly across the range on the strip and add them to your palette.
Send them through a prism
Open the wavelengths in your palette in the prism lab and see where each one lands on the screen.
Open the prism lab
Mixing light is not mixing screen colours
Choose two wavelengths and how much power each has. The left swatch adds the two spectra and converts the result once, which is how light mixes. The right swatch averages the two screen colours, which is not how light mixes. Paint and ink mix by absorbing light, which is different again: this demonstration does not apply to paint.
How the numbers work
Wavelength, frequency and photon energy
Light is an electromagnetic wave. Its wavelength in a vacuum, λ0, and its frequency, f, are linked by the speed of light. Each photon carries an energy set by its frequency, shown here in electronvolts:
f = c / λ0 E = h f EeV = h f / e
The constants are the exact SI values: c = 299 792 458 m/s, h = 6.626 070 15 × 10−34 J s and e = 1.602 176 634 × 10−19 C. A shorter wavelength means a higher frequency and more energy per photon: a 400 nm photon carries about 3.10 eV, a 700 nm photon about 1.77 eV. Values are rounded only for display.
Inside glass, light travels more slowly (c/n) and its wavelength shortens to λ0/n, but its frequency, and so the photon energy, stays the same. The wavelengths on this page are vacuum wavelengths.
| Wavelength | Frequency | Photon energy | Approximate region | Approximate screen colour |
|---|---|---|---|---|
| 380 nm | 788.9 THz | 3.263 eV | violet | #4F0099 |
| 400 nm | 749.5 THz | 3.100 eV | violet | #4E0099 |
| 420 nm | 713.8 THz | 2.952 eV | violet | #4D009A |
| 440 nm | 681.3 THz | 2.818 eV | violet | #4700A9 |
| 460 nm | 651.7 THz | 2.695 eV | blue | #0000DB |
| 480 nm | 624.6 THz | 2.583 eV | blue | #00798D |
| 500 nm | 599.6 THz | 2.480 eV | green | #00CAA8 |
| 520 nm | 576.5 THz | 2.384 eV | green | #00D882 |
| 540 nm | 555.2 THz | 2.296 eV | green | #00EF4B |
| 560 nm | 535.3 THz | 2.214 eV | green | #A1FC00 |
| 580 nm | 516.9 THz | 2.138 eV | yellow | #FAB600 |
| 600 nm | 499.7 THz | 2.066 eV | orange | #FE4900 |
| 620 nm | 483.5 THz | 2.000 eV | orange | #F40004 |
| 640 nm | 468.4 THz | 1.937 eV | red | #E60027 |
| 660 nm | 454.2 THz | 1.879 eV | red | #E0002D |
| 680 nm | 440.9 THz | 1.823 eV | red | #DF002F |
| 700 nm | 428.3 THz | 1.771 eV | red | #DE002F |
How far the visible spectrum goes
NASA describes visible light as roughly 380 to 700 nm, and that is the explorer’s starting range. The eye’s sensitivity fades gradually at both ends instead of stopping at a line. The 380–780 nm view is this explorer’s extended plotting range for looking at the dim deep-red end; it is not a new boundary of vision.
Colour names along the spectrum are conventional, approximate bands, and real colours blend into each other. The seven-name rainbow (red, orange, yellow, green, blue, indigo, violet) is a teaching tradition, not seven separate colours in the light.
| Region | From | To |
|---|---|---|
| Violet | 380 nm | 450 nm |
| Blue | 450 nm | 485 nm |
| Cyan | 485 nm | 500 nm |
| Green | 500 nm | 565 nm |
| Yellow | 565 nm | 590 nm |
| Orange | 590 nm | 625 nm |
| Red | 625 nm | 750 nm |
These are rounded bands chosen by PaintColorKE for labelling, in line with common textbook tables. Published tables differ by a few nanometres, and how a wavelength looks also depends on brightness and surroundings.
Spectral and non-spectral colours
A spectral colour is how light of a single wavelength looks. Many colours are not in the spectrum at all. Magenta needs short (violet-blue) and long (red) wavelengths together with little green in between, so no single wavelength looks magenta. White, greys, browns and pastels are mixtures too. The samples on this page are points along the spectrum, not a catalogue of every colour people can see.
Why the screen colours are approximate
A screen makes colours by mixing red, green and blue light; it cannot give out a single wavelength. Every colour of single-wavelength light lies outside the range (gamut) a typical sRGB screen can show. The explorer calculates each colour from the CIE 1931 2° colour-matching functions, converts it to sRGB as CSS Color 4 specifies, and brings it into the screen’s range by reducing its chroma in OKLCH, the CSS Color 4 gamut-mapping method.
The default hue preview scales every wavelength to a readable brightness. The equal energy view keeps the brightness that the same power of each wavelength would have, so the ends of the spectrum fade to dark. Neighbouring wavelengths can round to the same HEX code; they are still different wavelengths.
Why a paint colour has no single wavelength
Paint reflects a broad mix of wavelengths from the light that falls on it, and that mix changes with the light: daylight, warm bulbs or cool tubes. Very different mixtures can look the same. So a paint colour or a HEX code does not have “its” wavelength, and the explorer never turns a HEX code, photo or paint into a wavelength. Paint matches offered from your palette are approximate digital comparisons with the screen colour, not equivalent paints or mixing recipes.
Sources and data
- NASA Science, “Visible Light”
Owner’s reading reference. Introductory explanation and the approximate 380–700 nm range used as the teaching preset. - Britannica, “Color: The visible spectrum”
Owner’s reading reference, listed for further reading. No figures on these pages are taken from it. - Jack Westin, “Visual Spectrum Color”
Owner’s reading reference, listed for further reading. No figures on these pages are taken from it. - Gurukul Global, “Prismatic effect (Dispersion of Light by Prisms)”
Owner’s reading reference. Classroom prism explanation and Cauchy’s formula. Its oil-film colours are a different effect (see OpenStax). - CIE, CIE 1931 colour-matching functions, 2° observer (DOI 10.25039/CIE.DS.xvudnb9b)
The 1 nm table behind every approximate screen colour. Bundled unchanged; CC BY-SA 4.0. - CIE, Standard illuminant D65 (DOI 10.25039/CIE.DS.hjfjmt59)
The daylight model in the prism lab. Bundled unchanged; CC BY-SA 4.0. - NIST, SP 330 Section 2: the SI defining constants
Exact values of c, h and e used for frequency and photon energy. - W3C, CSS Color Module Level 4
XYZ to sRGB conversion and the gamut-mapping method used for every screen colour. - SCHOTT, TIE-29 Refractive Index and Dispersion (August 2023)
Snell’s law, the Sellmeier formula, its wavelength units and validity range. - SCHOTT optical glass data for N-BK7 and N-SF11 (Zemax catalogue 2017-01-20b, as listed by refractiveindex.info)
The published Sellmeier coefficients used for the two real glasses. - NASA Science, “Anatomy of an Electromagnetic Wave”
Wavelength, frequency and energy of electromagnetic waves. - MIT, Color Theory notes
Magenta as a non-spectral colour. - OpenStax, University Physics Volume 3, 3.4 Interference in Thin Films
Why oil and soap films are coloured: interference, not prism dispersion.
Screen colours are approximations for learning and design. They are not laboratory measurements, exact reproductions of spectral light or a calibration of your screen.