Short answer
No, though they are close neighbours. Cyan is a technical name first — the green-plus-blue secondary of screens and one of the process inks — and sits bluer and lighter; turquoise, named after the stone, sits greener. The CSS values are ΔE00 8.6 apart and the crowd's 16.2, and the regions share a band of hue around 190°–200°.
The lexicon gives cyan hues 190°–215° and lightness 0.78–0.95; turquoise gets 172°–200° and 0.65–0.88. The overlap is the light, bright corner where a blue-green is neither clearly one nor the other: 32% of cyan's sRGB colours are also turquoise, but only 18% of turquoise's are also cyan, because turquoise extends further down in lightness and further towards green. Measured on the reference swatches, cyan's hue is about 195° and turquoise's about 185°. The crowd survey widens the gap: its turquoise is darker and greener than the CSS keyword, while its cyan is exactly the screen primary.
On a screen, cyan is what you get by lighting the green and blue channels fully with no red: #00ffff, which CSS also calls 'aqua'. In printing, cyan is one of the process inks, a transparent blue-green that absorbs red light. The two are not the same colour. Process cyan printed on white paper is darker and less intense than the screen's cyan, and it cannot reproduce it; a screen, in turn, cannot always reproduce the exact ink. When a printer and a web developer both say 'cyan' they are naming the same role in two different mixing systems, not one swatch.
Turquoise came into English from French pierre turqueise, 'Turkish stone', because the mineral reached Europe through Turkish lands; it is recorded as a colour name from 1853. The mineral is a hydrated phosphate of copper and aluminium, and the stone itself varies between blue and green. So the name began with a range rather than a point. The CSS keyword (#40e0d0) is a bright, fairly light blue-green; the crowd's centre is deeper and greener, closer to the colour many people associate with south-western jewellery and tiles.
In a print or colour-management context, 'cyan' means the ink or the channel, and using it for a decorative colour invites confusion; say 'bright blue-green' or give a value instead. In interiors and fashion, turquoise is the natural word for a vivid light blue-green, with teal for the darker, muted version. For screen work, 'aqua' and 'cyan' are identical keywords in CSS, so pick one and never assume a difference between them. If a greener or bluer version matters, specify it in OKLCH hue, where a few degrees can be stated exactly.
| Cyan | Turquoise | Shared by both | |
|---|---|---|---|
| Lightness (L) | 0.78–0.95 | 0.65–0.88 | 0.78–0.88 |
| Chroma (C) | 0.100–0.170 | 0.090–0.160 | 0.100–0.160 |
| Hue (h) | 190°–215° | 172°–200° | 190°–200° |
| Reference swatch | #00ffff (L 0.91, C 0.155, h 195°) | #40e0d0 (L 0.82, C 0.131, h 185°) | ΔE00 8.6 apart |
| sRGB grid colours inside | 69 | 120 | 22 (32% of cyan, 18% of turquoise) |
| How settled the word is | moderate | moderate | — |
| Source of the value | Cyan | Turquoise | ΔE00 between them |
|---|---|---|---|
| CSS Color 4 named colour | #00ffff (L 0.91, C 0.155, h 195°) | #40e0d0 (L 0.82, C 0.131, h 185°) | 8.6 |
| Colourwise catalogue profile | #00ffff (L 0.91, C 0.155, h 195°) | #40e0d0 (L 0.82, C 0.131, h 185°) | 8.6 |
| xkcd colour survey | #00ffff (L 0.91, C 0.155, h 195°) | #06c2ac (L 0.73, C 0.131, h 181°) | 16.2 |
Why: Screen cyan lies outside what process cyan ink can reproduce on paper.
Fix: Define a separate print value or a spot colour, and approve it from a printed proof.
Why: They are the same CSS value.
Fix: Keep one token and give it a role name, not a colour name.
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.
StandardStrong evidence
CSS Color Level 4 defines cyan and aqua as the same value, #00ffff, and turquoise as #40e0d0.
Source: CSS Color Module Level 4
Colourwise analysisModerate evidence
The CSS cyan and turquoise values are 8.6 apart in CIEDE2000; the xkcd survey's cyan and turquoise are 16.2 apart.
Based on: CIEDE2000 computed by Colourwise from published sRGB values.
Caveat: CSS values are fixed conventions, not measurements of usage.
Source: CSS Color Module Level 4; Color survey results, and the rgb.txt list of the 954 most common colour names
FactModerate evidence
Turquoise derives from French pierre turqueise, 'Turkish stone', and is recorded as a colour name from 1853; cyan, from Greek kyanos ('dark blue'), is recorded from 1889 as short for 'cyan blue'.
Caveat: Dates are first recorded uses.
Source: Online Etymology Dictionary
Colourwise interpretationModerate evidence
'Cyan' names a role in a mixing system — a screen secondary or a process ink — more than a single colour, so screen cyan and printed cyan legitimately differ.
Based on: Additive screen cyan is full green plus blue light; process cyan is a subtractive ink absorbing red; the two are produced by different means and cover different gamuts.
Reviewed 29 September 2026. Colourwise summarises its sources in its own words and does not reproduce standards text or proprietary colour data. Spotted an error? Tell us.