What is RGB Color?
RGB Color (Red Green Blue) is an additive color model where red, green, and blue light are combined in various intensities to create a broad spectrum of colors. Each color channel typically ranges from 0 to 255, allowing for over 16 million possible color combinations.
Quick Facts
| Full Name | Red Green Blue Color Model |
|---|---|
| Created | 1931 (CIE RGB), digital use from 1950s |
| Specification | Official Specification |
How It Works
RGB is the standard color model for digital displays including monitors, TVs, and mobile screens. It's called 'additive' because colors are created by adding light - combining all three at full intensity produces white, while zero intensity produces black. In web development, RGB colors can be expressed as rgb(255, 0, 0) for red, or in hexadecimal as #FF0000. The RGBA variant adds an alpha channel for transparency. RGB is device-dependent, meaning the same RGB values may appear slightly different on different displays. Modern color spaces include OKLCH (perceptually uniform lightness, chroma, hue) which provides more intuitive color manipulation than HSL, and Display P3 which offers a wider gamut than sRGB for modern displays. CSS Color Level 4 introduces these color spaces with the color() function and oklch() notation.
Key Characteristics
- Additive color model (light-based)
- Three channels: Red, Green, Blue (0-255 each)
- Over 16 million colors (256³ = 16,777,216)
- Standard for digital displays and screens
- RGBA adds alpha channel for transparency
- Device-dependent color representation
Common Use Cases
- Web design and CSS styling
- Digital image editing
- Screen display and monitors
- LED lighting systems
- Video game graphics
Example
Loading code...Frequently Asked Questions
Why is RGB called an additive color model?
RGB is called additive because colors are created by adding light together. When red, green, and blue light are combined at full intensity, they produce white light. This is opposite to subtractive models like CMYK used in printing.
What is the difference between RGB and RGBA?
RGB uses three channels (Red, Green, Blue) with values from 0-255. RGBA adds a fourth channel called Alpha, which controls transparency with values from 0 (fully transparent) to 1 (fully opaque).
How do I convert RGB to hexadecimal color?
Convert each RGB value (0-255) to its two-digit hexadecimal equivalent. For example, rgb(255, 128, 0) becomes #FF8000, where FF=255, 80=128, and 00=0.
Why do the same RGB values look different on different screens?
RGB is device-dependent, meaning the actual color displayed depends on the display's color profile, brightness, contrast, and calibration. This is why color management and standardized color spaces like sRGB are important.
What is the total number of colors in the RGB model?
The standard 8-bit RGB model can represent 16,777,216 colors (256 × 256 × 256 = 16,777,216). This is often referred to as 24-bit color or true color.