Colors people ask about
Frequently asked questions
How do I find out what color a hex code is?
Paste the hex code into the box at the top of the page. Three formats all work:
- Six digits —
3972A4or#3972A4 - Three digits —
#39A, which expands to#3399AA - RGB —
rgb(57, 114, 164)
Every color also has its own page, so you can go straight to /color/3972a4 if you already know the code.
What if my hex code does not have a name?
Most do not, and that is normal. There are 16,777,216 possible hex codes and 24,648 named colors, so the overwhelming majority of colors have never been given a name by anyone.
When that happens we find the nearest color that does have a name, and label it a close match rather than an exact one. In practice the nearest name is very close — for a randomly chosen color the typical difference is about 1.2 ΔE, which is around the threshold most people can detect at all.
Where do the color names come from?
From five open sources. Nothing here is scraped from a competitor and nothing is invented by us:
| Source | What it is | Licence |
|---|---|---|
| CSS Color Level 4 | The 148 colour keywords browsers understand, like rebeccapurple | MIT |
X11 rgb.txt | The Unix colour list the web inherited its names from | MIT |
| Wikidata | Encyclopedic colours with sourced references | CC0 |
| xkcd Colour Survey | 949 names agreed on by roughly 200,000 people | CC0 |
| color-names | A curated community list, the source of most of the long tail | MIT |
Why does one color have several names?
Because different people named the same colour at different times. #00FFFF is Aqua in CSS and Cyan in X11 — both are correct.
We pick one name to lead with and keep the rest as aliases, listed on the colour’s page. The lead name is chosen by how authoritative the source is first — a browser keyword beats a community submission — then by how well the name reads.
What does ΔE mean?
ΔE (delta E) measures how far apart two colours look to a person, rather than how far apart their numbers are. We use the CIEDE2000 formula, which was fitted to actual human judgements.
| ΔE | What you would notice |
|---|---|
| 0 | Exactly the same colour |
| Under 1 | Nothing — below the threshold most eyes can separate |
| 1–2 | A difference only visible side by side |
| 2–5 | Clearly different if you compare them |
| Over 5 | Obviously two different colours |
Why not just compare the RGB numbers?
Because RGB numbers do not match how people see. The same numeric step is a large visible change among dark colours and almost invisible among light ones, and green contributes far more to brightness than blue does.
A tool that compares RGB directly gets dark colours wrong much more often than light ones. We convert to CIELAB first and compare there, which is why the answers hold up at both ends of the scale.
What is the difference between HEX, RGB and HSL?
They are three ways of writing the same colour:
| Format | How it describes a colour | Example |
|---|---|---|
| HEX | Red, green and blue as a six-digit code | #3972A4 |
| RGB | Red, green and blue as numbers from 0 to 255 | rgb(57, 114, 164) |
| HSL | Hue, saturation and lightness | hsl(207, 48%, 43%) |
All three describe the same colour. HEX is the most common on the web because it is compact and unambiguous.
Can I use these color names commercially?
Yes. Every name comes from a source that permits commercial use, with no share-alike or non-commercial restrictions attached.
A small number of names in the long tail were originally coined as trademarks by crayon and paint manufacturers. We keep those as aliases because they are what people actually search for, but we never present one as a colour’s primary name.
Why does the same color look different on my phone and my laptop?
Screens differ in brightness, calibration and colour profile, and features like night shift or true-tone change colours further. Two devices showing the same hex code can genuinely look different.
The code itself is exact, which is why it is worth working in hex rather than matching by eye.
How many named colors are there?
24,648 named colours, drawn from 32,726 distinct colours in the database. Every one has its own page, and you can browse all of them.
That still covers only about 0.15% of the 16.7 million possible hex codes — which is why the nearest-match answer matters more than the exact one.