# Radar chart

A radar chart plots several measures around a circle, one axis each. It is good for comparing two or three entities against the same criteria, and bad at almost everything else.

Area on a radar chart is meaningless, and reordering the axes changes the shape entirely. Use it knowingly.

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## When this is the right chart

* Comparing two or three options against fixed criteria.
* Capability or skill assessments.
* Scorecards where the axes are agreed in advance.

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## What the data needs to look like

| **Field** | **Type**                        |
| --------- | ------------------------------- |
| Criterion | Nominal: one axis each          |
| Value     | Quantitative, on a shared scale |
| Entity    | Nominal: one shape each         |

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## A worked example

Two candidate tools against five criteria:

![Radar chart](https://help.gocapable.com/images/att1417871511.svg)

The source, which you can paste into a new diagram and edit:

```
radar-beta
  title Tool evaluation
  axis speed["Speed"], cost["Cost"], support["Support"]
  axis ease["Ease of use"], sec["Security"]
  curve tool_a["Option A"]{85, 60, 70, 90, 65}
  curve tool_b["Option B"]{60, 85, 90, 55, 95}
  max 100
  min 0
```

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## A few things that catch people out

* Every axis must use the same scale, or the shape is meaningless.
* Two or three entities at most. Overlapping shapes become unreadable quickly.
* The order of the axes changes the shape. Agree it before anybody sees the chart.

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## Related

[Word cloudTerms sized by weight.](https://help.gocapable.com/diagrams/word-cloud.html)

[Bar chartComparing categories, sorted.](https://help.gocapable.com/diagrams/bar-chart.html)

[Charts and graphsBack to the chart overview.](https://help.gocapable.com/diagrams/charts-and-graphs.html)

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_Pick the chart for the question, not for the look._