Colors
Charts support three color options:
- for geometric elements, you can change background and border colors;
- for textual elements, you can change the font color.
Also, you can change the whole canvas background.
Default colors
If a color is not specified, a global default color from Chart.defaults
is used:
Name | Type | Description | Default value |
---|---|---|---|
backgroundColor | Color | Background color | rgba(0, 0, 0, 0.1) |
borderColor | Color | Border color | rgba(0, 0, 0, 0.1) |
color | Color | Font color | #666 |
You can reset default colors by updating these properties of Chart.defaults
:
Chart.defaults.backgroundColor = '#9BD0F5';
Chart.defaults.borderColor = '#36A2EB';
Chart.defaults.color = '#000';
Per-dataset color settings
If your chart has multiple datasets, using default colors would make individual datasets indistinguishable. In that case, you can set backgroundColor
and borderColor
for each dataset:
const data = {
labels: ['A', 'B', 'C'],
datasets: [
{
label: 'Dataset 1',
data: [1, 2, 3],
borderColor: '#36A2EB',
backgroundColor: '#9BD0F5',
},
{
label: 'Dataset 2',
data: [2, 3, 4],
borderColor: '#FF6384',
backgroundColor: '#FFB1C1',
}
]
};
However, setting colors for each dataset might require additional work that you’d rather not do. In that case, consider using the following plugins with pre-defined or generated palettes.
Default color palette
If you don’t have any preference for colors, you can use the built-in Colors
plugin. It will cycle through a palette of seven Chart.js brand colors:
All you need is to import and register the plugin:
import { Colors } from 'chart.js';
Chart.register(Colors);
Note
If you are using the UMD version of Chart.js, this plugin will be enabled by default. You can disable it by setting the enabled
option to false
:
const options = {
plugins: {
colors: {
enabled: false
}
}
};
Dynamic datasets at runtime
By default the colors plugin only works when you initialize the chart without any colors for the border or background specified. If you want to force the colors plugin to always color your datasets, for example when using dynamic datasets at runtime you will need to set the forceOverride
option to true:
const options = {
plugins: {
colors: {
forceOverride: true
}
}
};
Advanced color palettes
See the awesome list (opens new window) for plugins that would give you more flexibility defining color palettes.
Color formats
You can specify the color as a string in either of the following notations:
Notation | Example | Example with transparency |
---|---|---|
Hexadecimal (opens new window) | #36A2EB | #36A2EB80 |
RGB (opens new window) or RGBA (opens new window) | rgb(54, 162, 235) | rgba(54, 162, 235, 0.5) |
HSL (opens new window) or HSLA (opens new window) | hsl(204, 82%, 57%) | hsla(204, 82%, 57%, 0.5) |
Alternatively, you can pass a CanvasPattern (opens new window) or CanvasGradient (opens new window) object instead of a string color to achieve some interesting effects.
Patterns and Gradients
For example, you can fill a dataset with a pattern from an image.
const img = new Image();
img.src = 'https://example.com/my_image.png';
img.onload = () => {
const ctx = document.getElementById('canvas').getContext('2d');
const fillPattern = ctx.createPattern(img, 'repeat');
const chart = new Chart(ctx, {
data: {
labels: ['Item 1', 'Item 2', 'Item 3'],
datasets: [{
data: [10, 20, 30],
backgroundColor: fillPattern
}]
}
});
};
Pattern fills can help viewers with vision deficiencies (e.g., color-blindness or partial sight) more easily understand your data (opens new window).
You can use the Patternomaly (opens new window) library to generate patterns to fill datasets:
const chartData = {
datasets: [{
data: [45, 25, 20, 10],
backgroundColor: [
pattern.draw('square', '#ff6384'),
pattern.draw('circle', '#36a2eb'),
pattern.draw('diamond', '#cc65fe'),
pattern.draw('triangle', '#ffce56')
]
}],
labels: ['Red', 'Blue', 'Purple', 'Yellow']
};