---
title: "Hexbin"
description: "Binned 2D density. What the hexbin is for, the data it needs and every option it has."
section: "Widgets"
canonical: "https://banksync.io/docs/widgets/chart-hexbin"
specs: ["dashboards"]
operationBindings: [{"capability":"dashboards","operation":"dashboards.author"}]
---

Binned 2D density. It sits in the **Correlation** group of the widget library.

![Example hexbin on a BankSync dashboard](https://cdn.banksync.io/screenshots/docs/charts/hexbin.76c3a3d7243a2a4a.png)

## When to use it

Use a hexbin to see where thousands of data points cluster when a scatter plot would turn into a solid blob. Plot two numbers against each other, such as transaction amount against day of the month. Darker hexagons hold more points.

## When to pick something else

- Only a few hundred points, where individual dots matter? Use a **Scatter plot**.
- A smooth outline of where points concentrate? Use a **Contour**.
- The spread of a single number? Use a **Histogram**.
- Counts across two categories, such as weekday against hour? Use a **Heatmap** or **Punchcard**.

## The data it needs

Pick these in the **Data** tab of the inspector. BankSync suggests a column for each when your source has an obvious match.

| Field      | Needed   | Pick       | Notes |
| ---------- | -------- | ---------- | ----- |
| **X axis** | Yes      | a number   |       |
| **Y axis** | Yes      | a number   |       |
| **Size**   | Optional | a number   |       |
| **Color**  | Optional | a category |       |

Each row is drawn as it is, so shape the rows first if you need totals. See [Shaping data](/docs/dashboards/dashboards-shaping-data).

## Hexbin options

This chart has no options of its own; everything on its **Style** tab is the shared chart styling below.

## Shared chart styling

Every chart also has the shared styling options. These apply to this one:

- [Legend](/docs/widgets/chart-styling#legend): position, layout and which series show.
- [Axes](/docs/widgets/chart-styling#axes): titles, tick labels and number format.
- [Grid](/docs/widgets/chart-styling#grid), [title](/docs/widgets/chart-styling#title), [padding](/docs/widgets/chart-styling#padding) and [background](/docs/widgets/chart-styling#background).
- [Value labels](/docs/widgets/chart-styling#value-labels) on the marks.
- [Categories and labels](/docs/widgets/chart-styling#categories-and-labels): top N with "Other", sort order, readable labels, the handwritten callout.
- [Style](/docs/widgets/chart-styling#style): corner radius, line width, opacity and animation.
- [Tooltip](/docs/widgets/chart-styling#tooltip) on hover.
- [Colours](/docs/widgets/chart-styling#palette): follow the dashboard palette or pick one for this chart.

## Messy data

- Both fields must be numbers. Rows where either is blank or not a number, including dates and text, are skipped. If nothing is left you see "No numbers to show".
- Colour shows how many points fall in each hexagon, not their total value. Hover a hexagon to see its count and ranges.
- A single extreme value stretches the axes and squeezes everything else into a few hexagons. Filter outliers out first.

## On a phone

On a phone the hexagons scale with the card, so the pattern survives, but each hexagon covers a wider range. The "Less … More" colour key stays under the plot unless the card is very small.

## Related charts

- [Bubble chart](/docs/widgets/chart-bubble): Scatter sized by a field
- [Contour](/docs/widgets/chart-contour): 2D density contours
- [Parallel coordinates](/docs/widgets/chart-parallel-coords): Multi-dimensional comparison