---
title: Handlebars Chart
hide_title: true
sidebar_position: 10
version: 1
---

## Handlebars Chart

The Handlebars chart lets you render query results using a custom [Handlebars](https://handlebarsjs.com/) template. This gives you full control over how your data is displayed — from simple tables to rich HTML layouts.

### Basic Usage

In the chart editor, write a Handlebars template in the **Template** field. Your query results are available as `data`, an array of row objects.

```handlebars
{{#each data}}
  <p>{{this.name}}: {{this.value}}</p>
{{/each}}
```

### Built-in Helpers

Superset registers several custom helpers on top of the standard Handlebars built-ins.

#### `dateFormat`

Formats a date value using [Day.js](https://day.js.org/) format strings.

```handlebars
{{dateFormat my_date format='MMMM YYYY'}}
```

| Option   | Default      | Description                       |
| -------- | ------------ | --------------------------------- |
| `format` | `YYYY-MM-DD` | A Day.js-compatible format string |

---

#### `stringify`

Converts an object to a JSON string, or any other value to its string representation.

```handlebars
{{stringify myObj}}
```

---

#### `formatNumber`

Formats a number using locale-aware formatting.

```handlebars
{{formatNumber myNumber 'en-US'}}
```

| Option   | Default | Description           |
| -------- | ------- | --------------------- |
| `locale` | `en-US` | A BCP 47 language tag |

---

#### `parseJson`

Parses a JSON string into an object that can be used in your template.

```handlebars
{{parseJson myJsonString}}
```

---

#### `groupBy`

Groups an array of objects by a key, powered by [handlebars-group-by](https://github.com/nicktindall/handlebars-group-by).

```handlebars
{{#groupBy data 'department'}}
  <h3>{{value}}</h3>
  {{#each items}}
    <p>{{this.name}}</p>
  {{/each}}
{{/groupBy}}
```

---

### Helpers from just-handlebars-helpers

Superset also registers all helpers from the [just-handlebars-helpers](https://github.com/leapfrogtechnology/just-handlebars-helpers) library. These include a wide range of comparison, math, string, and conditional helpers. Commonly used ones include:

#### Comparison

| Helper | Description           | Example                        |
| ------ | --------------------- | ------------------------------ |
| `eq`   | Strict equality       | `{{#if (eq status "active")}}` |
| `eqw`  | Weak equality         | `{{#if (eqw count "5")}}`      |
| `neq`  | Strict inequality     | `{{#if (neq role "admin")}}`   |
| `lt`   | Less than             | `{{#if (lt score 50)}}`        |
| `lte`  | Less than or equal    | `{{#if (lte score 100)}}`      |
| `gt`   | Greater than          | `{{#if (gt price 0)}}`         |
| `gte`  | Greater than or equal | `{{#if (gte age 18)}}`         |

#### Logical

| Helper     | Description                   | Example                                  |
| ---------- | ----------------------------- | ---------------------------------------- |
| `and`      | Logical AND                   | `{{#if (and isActive isVerified)}}`      |
| `or`       | Logical OR                    | `{{#if (or isAdmin isMod)}}`             |
| `not`      | Logical NOT                   | `{{#if (not isDisabled)}}`               |
| `ifx`      | Inline conditional            | `{{ifx isActive "Yes" "No"}}`            |
| `coalesce` | Returns first non-falsy value | `{{coalesce nickname name "Anonymous"}}` |

#### String

| Helper       | Description                         | Example                           |
| ------------ | ----------------------------------- | --------------------------------- |
| `capitalize` | Capitalizes first letter            | `{{capitalize name}}`             |
| `uppercase`  | Converts to uppercase               | `{{uppercase status}}`            |
| `lowercase`  | Converts to lowercase               | `{{lowercase email}}`             |
| `truncate`   | Truncates a string                  | `{{truncate description 100}}`    |
| `contains`   | Checks if string contains substring | `{{#if (contains tag "urgent")}}` |

#### Math

| Helper     | Description    | Example                       |
| ---------- | -------------- | ----------------------------- |
| `add`      | Addition       | `{{add a b}}`                 |
| `subtract` | Subtraction    | `{{subtract total discount}}` |
| `multiply` | Multiplication | `{{multiply price quantity}}` |
| `divide`   | Division       | `{{divide total count}}`      |
| `ceil`     | Ceiling        | `{{ceil value}}`              |
| `floor`    | Floor          | `{{floor value}}`             |
| `round`    | Round          | `{{round value}}`             |

For the full list of available helpers, see the [just-handlebars-helpers documentation](https://github.com/leapfrogtechnology/just-handlebars-helpers).

### Tips

- Use raw blocks to escape Handlebars syntax if you need to display double curly braces literally.
- Comparison helpers like `eq` must be wrapped in a subexpression when used with `#if`: `{{#if (eq myVal "foo")}}`.
- HTML output is sanitized by default based on your Superset configuration (`HTML_SANITIZATION`).
