An 8-digit hexadecimal code used to define a color's Red, Green, Blue, and Opacity (Alpha). A standard hex code uses 6 digits (#RRGGBB). Adding two extra digits at the end (#RRGGBBAA) controls the transparency level. Range: 00 (0% opacity/fully transparent) to FF (100% opacity/fully opaque). Math: The alpha value is a 0-255 scale mapped to a percentage.
Common Opacity Conversions
If you want to quickly add transparency to a color, use these common hex suffixes:
- 100%: FF
- 75%: BF
- 50%: 80
- 25%: 40
- 0%: 00
Browser Support
While modern browsers (Chrome 62+, Safari 10+, Firefox 52+) fully support 8-digit hex codes, older legacy systems may require rgba() functional notation instead.
Table: Opacity Examples
| Opacity | Hex Suffix | Example (#Red) |
| 100% | FF | #FF0000FF |
| 75% | BF | #FF0000BF |
| 50% | 80 | #FF000080 |
| 25% | 40 | #FF000040 |
| 0% | 00 | #FF000000 |
