Colors

You can use specify fill and line colors either:

with its standard name or CSS name
using HEX value (6 digits): #RRGGBB
using HEX value (8 digits) with alpha compositing or RGBA color model: #RRGGBBaa
using short HEX value (3 digits): #RGB

@startgantt
[Activity1] lasts 5 days
[Activity2] lasts 5 days
[Activity1] is colored in White/Red
[Activity2] is colored in Silver/SeaGreen
[Activity1] -> [Activity2]
@endgantt

Example Sequence Diagram:

@startuml
actor Bob #Red/Yellow
actor Alice #FF0000/FFFF00
Alice -> Bob : hello
@enduml

Also see: skinparam

Color gradient

You can also use color gradient in background, with the following syntax: two colors names separated either by:

|,
/,
\,
or -

depending the direction of the gradient.

See Color gradient on Class diagram page.

Automatic color

The special value automatic can be used for text. In that case, the color is either black or white, depending on the current background.

@startuml
skinparam classFontColor automatic
skinparam classHeaderBackgroundColor #444

class classA {
testMethodCode()        
}

class classB #fff {
testMethodCode()       
}
@enduml

View colors in PlantUML

A user has recently created an image to display all names colors used by PlantUML. (We thank him by the way!)

So a new feature has been added to print all those colors using a special diagram description:

@startuml
colors
@enduml

It is also possible to print a palette of colors close to some other color (using its name or HEX value).

@startuml
colors chocolate
@enduml