# Radar Chart

A radar chart, also known as a spider or web chart, plots multivariate data on a series of axes radiating from a central point - one axis per variable. Data values are plotted along each axis and connected to form a polygon, making it easy to see the overall "shape" of a profile at a glance.

Radar charts excel at comparing performance or characteristics across multiple dimensions simultaneously.

###### Site Earnings

Chart with 4 data series.

Earnings by site, for the first week of January

The chart has 1 X axis displaying categories.

The chart has 1 Y axis displaying values. Data ranges from 482.63 to 23193.08.

## Creating an Effective Radar Chart

Recommended data types for each axis:

- **X-Axis** Categorical data (each category becomes one spoke of the radar)
- **Y-Axis** Numerical values
- **Breakdown Axis** Categorical data (each unique value becomes a separate polygon)

## Description

- **Spokes** - equi-angular axes radiating from the center; each spoke represents one variable
- **Polygons** - values along the spokes are connected to form a shape; a larger, rounder polygon indicates uniformly high values
- **Center** - represents the minimum or zero value; outer ring represents the maximum
- **Colors** - when multiple series are plotted, each polygon uses a distinct color with semi-transparent fill
- **Legend** - maps each color to its corresponding series

## Ideal Data for Radar Charts

Radar charts work best when your data has:

- **3–10 variables** - fewer than 3 variables doesn’t benefit from the radial layout; more than 10 spokes becomes crowded
- **Comparable scales** - variables should be on similar scales or normalized so no single spoke dominates visually
- **Related metrics** - the dimensions should belong to the same conceptual group (e.g., skill categories, product attributes)

## When to Use a Radar Chart

- **Performance profiles** - compare strengths and weaknesses across multiple attributes for one or more subjects
- **Skill assessments** - visualize competency scores across different areas for a person or team
- **Product comparisons** - contrast specifications or feature ratings across multiple products
- **Before/after comparisons** - overlay two polygons to show how performance changed across all dimensions

## When to Avoid a Radar Chart

- **Precise value comparisons** - angular area is hard to read accurately; use a [bar chart](https://instacharts.io/docs/chart-types/bar-chart/) when exact differences matter
- **More than 2–3 series** - overlapping polygons become indistinguishable with many series
- **Variables on very different scales** - without normalization, one spoke will overwhelm the rest and distort the shape
- **Ordered or time-series data** - use a [line chart](https://instacharts.io/docs/chart-types/line-chart/) when the X-axis has a meaningful sequence