HTML color names are predefined keywords that represent specific colors in web development. Instead of using hex codes like #FF0000 or RGB values, you can simply write red, blue, or tomato in your CSS and HTML. These named colors are officially recognized by the W3C and are supported across all modern browsers. There are currently 148 named colors in the CSS specification (including rebeccapurple added in CSS Color Level 4).

There are 148 standard named colors in CSS (CSS Color Module Level 4). This includes the original 16 HTML 4.01 colors, 130 extended colors from the X11/SVG palette, and rebeccapurple (#663399) — a special addition honoring Rebecca Meyer. Additionally, several colors have alternate spellings (e.g., Gray / Grey), bringing the total recognized keywords to over 150. Note that transparent and currentColor are also valid CSS color keywords but don't map to specific hex values.

No. HTML and CSS color names are completely case-insensitive. You can write AliceBlue, aliceblue, ALICEBLUE, or even aLiCeBlUe — they all work the same. However, the conventional and most readable format is PascalCase (e.g., AliceBlue, LightSkyBlue), which is how they're listed in official specifications and our tool above.

Color names are great for readability and quick prototyping — tomato is more intuitive than #FF6347. They're ideal for basic colors like white, black, or red. However, hex codes offer far more precision (16.7 million colors vs. 148 named ones), are universally understood by design tools, and are preferred in production code for consistency. Many developers use named colors for quick drafts and replace them with hex/RGB values in final builds.

Yes. All 148 standard CSS color names are supported in every modern browser — Chrome, Firefox, Safari, Edge, and Opera — going back many versions. The core 16 colors have been supported since the earliest days of the web (HTML 4.01, 1999). The extended 130 X11 colors gained universal support by the early 2010s. rebeccapurple was added in 2014 and is now supported everywhere. You can safely use any named color in production websites without compatibility concerns.

The 16 original HTML 4.01 colors are: Aqua (#00FFFF), Black (#000000), Blue (#0000FF), Fuchsia (#FF00FF), Gray (#808080), Green (#008000), Lime (#00FF00), Maroon (#800000), Navy (#000080), Olive (#808000), Purple (#800080), Red (#FF0000), Silver (#C0C0C0), Teal (#008080), White (#FFFFFF), and Yellow (#FFFF00). These were the only named colors guaranteed to work across all early browsers.

rebeccapurple (#663399) is a heartfelt tribute to Rebecca Meyer, the daughter of prominent CSS developer Eric Meyer. Rebecca passed away from brain cancer in 2014 at age 6, and purple was her favorite color. The CSS community rallied to honor her memory by adding this color to the official CSS Color Module Level 4 specification. It's the first named color added to the web standard since the original X11 colors, and serves as a touching reminder of the human stories behind web standards.

Color names alone don't support alpha transparency. However, you can combine them with CSS functions: use rgba(255, 99, 71, 0.5) for semi-transparent tomato, or modern syntax like rgb(from tomato r g b / 0.5) in CSS Color Level 5 (still gaining browser support). For now, if you need transparency, you'll need to convert the named color to its RGB or hex equivalent and use rgba() or 8-digit hex like #FF634780.