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---
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}}
```
---
#### `group`
Groups an array of objects by a key, powered by [handlebars-group-by](https://github.com/nicktindall/handlebars-group-by). The key is passed as a `by` hash argument.
```handlebars
{{#group data by="department"}}
<h3>{{value}}</h3>
{{#each items}}
<p>{{this.name}}</p>
{{/each}}
{{/group}}
```
---
### 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:
:::note
These names are specific to `just-handlebars-helpers` and differ from other
Handlebars helper libraries — notably `handlebars-helpers`, which spells the
math helpers `add`, `subtract`, `multiply` and `divide`. Calling a helper that
is not registered raises `Missing helper: "..."`, which renders the chart blank,
so it is worth checking a name against the tables below before using it.
:::
#### 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")}}` |
| `neqw` | Weak inequality | `{{#if (neqw count "5")}}` |
| `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 |
| ----------------- | ----------------------------------------------- | ------------------------------ |
| `capitalizeFirst` | Capitalizes the first letter | `{{capitalizeFirst name}}` |
| `capitalizeEach` | Capitalizes the first letter of each word | `{{capitalizeEach title}}` |
| `uppercase` | Converts to uppercase | `{{uppercase status}}` |
| `lowercase` | Converts to lowercase | `{{lowercase email}}` |
| `excerpt` | Truncates to a length and appends an ellipsis | `{{excerpt description 100}}` |
| `sprintf` | printf-style formatting | `{{sprintf "%.1f" score}}` |
| `concat` | Concatenates values | `{{concat first " " last}}` |
| `join` | Joins an array with a separator | `{{join tags ", "}}` |
| `first` / `last` | First or last element of an array | `{{first items}}` |
| `newLineToBr` | Converts newlines to `<br>` (needs `{{{ }}}`) | `{{{newLineToBr notes}}}` |
#### Math
| Helper | Description | Example |
| ---------------- | ----------------------- | ------------------------------------ |
| `sum` | Addition | `{{sum a b}}` |
| `difference` | Subtraction | `{{difference total discount}}` |
| `multiplication` | Multiplication | `{{multiplication price quantity}}` |
| `division` | Division | `{{division total count}}` |
| `remainder` | Modulo | `{{remainder index 2}}` |
| `abs` | Absolute value | `{{abs delta}}` |
| `ceil` | Ceiling | `{{ceil value}}` |
| `floor` | Floor | `{{floor value}}` |
`sum` takes exactly two arguments — it adds a pair of numbers and does not total
an array. There is no `round` helper; use `{{sprintf "%.0f" value}}` to round to
a given number of decimal places.
#### Arrays
| Helper | Description | Example |
| ---------- | ---------------------------------- | --------------------------------- |
| `includes` | Whether an array contains a value | `{{#if (includes tags "urgent")}}` |
| `empty` | Whether an array is empty | `{{#if (empty rows)}}` |
| `count` | Number of items in an array | `{{count rows}}` |
`includes` tests array membership. It returns `false` for a string, so it cannot
be used to check for a substring.
#### Formatting
| Helper | Description | Example |
| ---------------- | ---------------------------- | -------------------------------- |
| `formatCurrency` | Formats a number as currency | `{{formatCurrency revenue "$"}}` |
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`).