MJML Bar Chart

Getting started

First you'll have to install mjml-bar-chart in your project.

npm install --save mjml mjml-core mjml-bar-chart

Then import it and manually register the plugin.

with ESM:

import { registerComponent } from "mjml-core";
import MjBarChart from "mjml-bar-chart";

registerComponent(MjBarChart, { registerDependencies: true });

with CJS:

const { registerComponent } = require("mjml-core");
const MjBarChart = require("mjml-bar-chart").default;

registerComponent(MjBarChart, { registerDependencies: true });

Set the registerDependencies option to true to automatically declare the mj-bar-chart component dependencies to the mjml-validator module.

You can now use the mjml-bar-chart component in your MJML templates:

<mjml>
  <mj-body>
    <mj-section>
      <mj-column>
        <mj-bar-chart>
          {
            "title":"Sum of Requests by Department",
            "datasets":["January","February","March"],
            "series":[
              {"label":"support","color":"#d8f3dc","data":[33,18,7]},
              {"label":"sales","color":"#95d5b2","data":[14,66,15]},
              {"label":"tech","color":"#52b788","data":[27,42,21]}
            ]
          }
        </mj-bar-chart>
      </mj-column>
    </mj-section>
  </mj-body>
</mjml>

Yay, you're all set!

Customize

Content

The <mj-bar-chart> content must be a valid JSON string with the following structure:

{
  "title": "Annual offset mix in tCO2",
  "source": {
    "url": "#trustmebro",
    "label": "Source: TrustMeBro ↗"
  },
  "datasets": ["2021", "2022", "2023", "2024", "2025"],
  "series": [
    {
      "label": "commute",
      "color": "#adb2d4",
      "data": [3.7,7.5,4.3,15,6.9]
    },
    {
      "label": "travels",
      "color": "#c7d9dd",
      "data": [13.4,7.2,11,20.4,13.2]
    },
    {
      "label": "carbon balance",
      "color": "#d5e5d5",
      "data": [23.4,12.1,40.5,38.1,4]
    },
    {
      "label": "others",
      "color": "#eef1da",
      "data": [4.9,15.2,-4.5,18.8,7]
    }
  ]
}

Note that all negative values will be floored to zero.

If you're using TypeScript you can import the Chart interface to validate your data structure.

import type { Chart } from "mjml-bar-chart";

const chart: Chart = {...}

Built-in properties

All the following attributes are optional

attribute	coerced type	default value	description
uid	string	""	Applies a suffix to chart CSS classes. Useful when styling multiple charts in the same email
stacked	boolean	"false"	Whether to stack dataset values in a single column
font-family	string	"inherit"	Font family to apply to every text element. Can also be set from <mj-all> markup
axis-color	string	"#d4d4d4"	CSS color of axis and scale numbers
height	number	"200"	Chart height in pixel
bar-width	number	"30"	Bar width in pixel
separator-width	number	"30"	Datasets separator width in pixel
step-count	number	"5"	Step number on the chart scale, below 2 no steps will be displayed
show-values	boolean	"true"	Whether it should display values above each bar
align-legends	boolean	"false"	Whether it should vertically align legend labels
max-width	number	"600"	The max width the chart should take. If it overflows bar-width and separator-width are dynamically computed to fit

Dynamic resizing when data overflows

Providing the chart attribute max-width is strongly advised as the graph will automatically resize to fit when data require expanding beyond this threshold.

When the limit is overreached the graph will automatically set the step-count to 0 to hide the y-axis to gain space and will dynamically recompute the bar-width and separator-width to fit the limited width.

Styling through CSS classes

Bar charts are generated with predefined classes that you can use for styling with custom CSS.
There are two ways of providing CSS overrides for your email charts:

• mj-class: (recommended) style will be dynamically retrieved and injected into the style attribute for high-priority override.
• mj-style: to provide a custom CSS declaration that will be applied with a low priority (will not override the CSS set from style attributes).

These are all the generated classes that you can use:

• mjbc: the class of the chart root element.
• mjbc__title: the class of the chart title text.
• mjbc__source: the class of the chart source link.
• mjbc__label: the class of the chart labels.
• mjbc__legend: the class of the chart legends.
• mjbc__step: the class of the chart steps.
• mjbc__bar: the class of the chart bars.

With their location in the generated chart:

If you have multiple charts in the same email, you can pass a unique identifier to each one to be able to apply different styles.
Class mjbc will become mjbc<uid>, mjbc__title will become mjbc<uid>__title, and so on.

For example:

<mjml>
  <mj-head>
    <mj-attributes>
      <mj-class name="mjbc1__title" color="lightcoral" font-weight="bold"/>
      <mj-class name="mjbc2__title" color="rebeccapurple" font-family="Menlo"/>
    </mj-attributes>
  </mj-head>
  <mj-body>
    <mj-section>
      <mj-column>
        <mj-bar-chart uid="1">{{ JSON.stringify(jsonChart1) }}</mj-bar-chart>
        <mj-bar-chart uid="2" stacked align-legends>
          {{ JSON.stringify(jsonChart2) }}
        </mj-bar-chart>
      </mj-column>
    </mj-section>
  </mj-body>
</mjml>