---
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`).
