HEX to RGBA
Convert 6- and 8-digit HEX colors to CSS rgba() with alpha.
Type a HEX value or pick a color – the result updates instantly.
Preview
HEX to RGBA Converter
This converter turns HEX color codes – including the 8-digit form with a built-in alpha byte – into a CSS rgba() value. Enter #1E90FF80 and you get rgba(30, 144, 255, 0.502): the same Dodger Blue at roughly half opacity. Six-digit codes convert with an alpha of 1, and the result table also shows HEX with alpha, HSL, HSV, and CMYK.
Reading the alpha byte
An 8-digit HEX code is #RRGGBBAA. The first six digits are the color, and the final pair is opacity on a 0–255 scale. To get the decimal alpha that rgba() expects, divide that byte by 255. Four-digit shorthand works the same way: #F608 expands to #FF660088, which is rgba(255, 102, 0, 0.533).
| Alpha HEX | Byte | rgba() alpha |
|---|---|---|
| 00 | 0 | 0 |
| 33 | 51 | 0.2 |
| 40 | 64 | 0.251 |
| 80 | 128 | 0.502 |
| BF | 191 | 0.749 |
| CC | 204 | 0.8 |
| FF | 255 | 1 |
Worked example
Take #1E90FF80. Split it into pairs: 1E = 1 × 16 + 14 = 30, 90 = 9 × 16 = 144, FF = 255, and the alpha pair 80 = 128. Dividing 128 by 255 gives 0.502, so the CSS value is rgba(30, 144, 255, 0.502). If you want a clean 0.5, write the rgba() value by hand – the HEX form cannot represent exactly 50%.
Where RGBA is the better choice
- Overlays and scrims: a dark layer like
rgba(0, 0, 0, 0.6)over a hero image is easier to adjust than#00000099. - Shadows:
box-shadowvalues are usually tuned by the alpha number, not by a hex pair. - Design handoff: tools such as Figma export 8-digit HEX, while many style guides and JavaScript canvas code use
rgba().
Need to go the other way? The RGB to HEX converter accepts rgba() input and produces an 8-digit code. For plain opaque colors, the HEX to RGB page is all you need.
Frequently Asked Questions
How is the alpha channel of an 8-digit HEX code converted?
The last two digits are read as a number from 0 to 255 and divided by 255. For #1E90FF80, 80 in hex is 128, and 128 / 255 = 0.502, so the result is rgba(30, 144, 255, 0.502).
What alpha do I get from a 6-digit HEX code?
A 6-digit code has no transparency information, so it is treated as fully opaque and converts with an alpha of 1, for example #1E90FF becomes rgba(30, 144, 255, 1).
Why is 80 not exactly 50% opacity?
The alpha byte has 256 steps (0 to 255), and 50% of 255 is 127.5, which is not a whole number. The closest bytes are 7F (0.498) and 80 (0.502), so neither is exactly 0.5.
Do browsers support 8-digit HEX colors directly?
Yes, all current browsers accept #RRGGBBAA and #RGBA in CSS. Converting to rgba() is still useful for older tooling, for readability, and for code that expects a decimal alpha value.