What colour is chartreuse?

Halfway in numbers, nearer green to the eye

The CSS keyword sets red to 127, green to 255 and blue to 0: exactly between pure green (red 0) and pure yellow (red 255). That is where the idea of chartreuse as 'half yellow, half green' comes from. Colour difference tells a different story. From CSS chartreuse it is ΔE00 5.1 to the green primary and 18.6 to yellow, because equal steps in the red channel are not equal steps in appearance: adding red to green changes little at first and a great deal near the yellow end. In OKLCH the CSS value has a hue of 136°, against about 142° for the green primary and 110° for yellow. The crowd's chartreuse (#c1f80a) is yellower, at 124°, and ΔE00 8.3 from the CSS value.

A liqueur's name, borrowed in 1884

Chartreuse is the liqueur made by Carthusian monks, whose chief monastery, la Grande-Chartreuse, takes its name from a mountain massif in the French Alps. The drink's name is recorded in English from 1866. The colour name followed in 1884 and, according to the etymology source, referred to the pale apple-green of the best grade of the liqueur. That is worth noticing, because 'pale apple-green' is not what the word means now. The CSS value and the crowd's are both close to as saturated as a standard screen can show. Like mauve, which went from a strong dye to a soft purple, chartreuse has drifted from its source, in the opposite direction: from a pale green to a highly saturated yellow-green.

Chartreuse and lime name almost the same colours

The lexicon's chartreuse region covers hues 118°–138° and lime's 120°–145°, at similar lightness and chroma. 85% of chartreuse lies inside lime, and 38% of lime inside chartreuse; the CSS and survey values for each name fall inside both regions, except that CSS lime, the green primary itself, is lime only. The two words differ in register more than in colour. In the published values lime leans a little greener and chartreuse a little yellower; in Colourwise's reading lime is the everyday word and chartreuse the one design and fashion writing reaches for. Neither belongs to a basic term: 2% of chartreuse's colours fall inside the lexicon's green and 0% inside yellow, which makes yellow-green another gap English fills only with secondary names.

Korean gives this area a basic term of its own, yeondu, kept apart from the word for green.

The CSS yellow-greens do not line up by name

CSS has seven keywords between yellow and green, and their names are a poor guide to their order. The table lists them with their distance from chartreuse. 'Lawngreen' is all but identical to chartreuse, ΔE00 0.7 away, a difference too small to see. 'Greenyellow' is the yellower neighbour. 'Yellowgreen' and 'limegreen' sound as if they belong beside them but are much darker, outside the chartreuse region and inside the lexicon's green. The pair worth remembering is that CSS 'lime' is the pure green primary, greener than anything most people would call lime, so a stylesheet's lime is greener than the crowd survey's lime, and CSS chartreuse lies between the two.

Using a colour this light and this strong

Chartreuse is unusual in being both very saturated and very light: the CSS value has an OKLCH lightness of 0.89, close to white's. That has two practical consequences. Against white it has almost no contrast, a ratio of 1.30:1, so chartreuse text or thin lines on a white page disappear; against black the ratio is 16.2:1, so it works as a highlight on dark backgrounds. The CSS value is also at the limit of sRGB, with its green channel at maximum and its blue at zero: a standard display has no more saturated version of that hue to offer, and any conversion to a smaller colour range, print included, has to bring it inwards. Check a printed proof before committing a brand colour to it.

The data

What goes wrong, and what to do

What the evidence says

Each statement is labelled by kind — established fact, a standard’s requirement, observed market data, a convention, or Colourwise’s own interpretation or analysis — with the strength of the evidence behind it.

• Colourwise analysisModerate evidence

  CSS chartreuse (#7fff00) is 5.1 ΔE00 from the sRGB green primary (#00ff00) and 18.6 from sRGB yellow (#ffff00), although its red channel is midway between theirs.

  Based on: CIEDE2000 computed by Colourwise from the sRGB values of the three CSS keywords.

  Source: CSS Color Module Level 4

• StandardStrong evidence

  CSS Color Level 4 defines chartreuse as #7fff00 and lawngreen as #7cfc00, and defines lime as #00ff00, the full sRGB green primary.

  Source: CSS Color Module Level 4

• FactModerate evidence

  Chartreuse, the liqueur of the Carthusian monks of la Grande-Chartreuse, is recorded in English from 1866; the colour name dates from 1884 and referred to the pale apple-green of the best type of the liqueur.

  Caveat: Summarised from a compiled etymology reference; first-attestation dates can move.

  Source: Online Etymology Dictionary

• Colourwise analysisModerate evidence

  CSS chartreuse has a contrast ratio of 1.30:1 against white and 16.2:1 against black.

  Based on: WCAG relative-luminance contrast ratio computed by Colourwise from the sRGB values.

  Source: CSS Color Module Level 4

• Colourwise interpretationLimited evidence

  The word chartreuse has moved from a pale, muted green to a highly saturated yellow-green since it was coined.

  Based on: The etymology source describes the original reference as pale apple-green; the CSS and crowd-survey values both have OKLCH chroma above 0.22.

  Caveat: Rests on one dictionary's description of the 1884 sense and two present-day screen values; paint and textile usage is softer.

Related questions

Is chartreuse green or yellow?

Green, by a clear margin, when measured: the CSS value is about 3.6 times as far from yellow as from the green primary. In RGB numbers it sits exactly between them, which is where the 'half and half' description comes from.

Is chartreuse the same as lime green?

Very nearly, in everyday use. In the lexicon most of chartreuse's region lies inside lime's. Chartreuse tends to mean a slightly yellower colour and is the term fashion and design writing prefers.

Why is the colour called chartreuse?

After the liqueur made by Carthusian monks at la Grande-Chartreuse in the French Alps. The colour name is recorded from 1884 and originally referred to the pale green of the best grade of the drink.

Related topics

Go further

Sources

• CSS Color Module Level 4 — W3C (World Wide Web Consortium) (Official standard or government)
• Online Etymology Dictionary — Douglas Harper (Reference work)
• Color survey results, and the rgb.txt list of the 954 most common colour names — xkcd (Randall Munroe) (Reference work)
• Colourwise editorial synthesis — Colourwise (Colourwise editorial)

Reviewed 1 October 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.