PIE CHART in ggplot2

Sample data

The following data frame contains a numerical variable representing the count of some event and the corresponding label for each value.

df <- data.frame(value = c(10, 23, 15, 18),
                 group = paste0("G", 1:4))

value	group
10	G1
23	G2
15	G3
18	G4

Basic pie chart with `geom_bar` or `geom_col` and `coord_polar`

Basic pie chart

A pie chart in ggplot is a bar plot plus a polar coordinate. You can use geom_bar or geom_col and theta = "y" inside coord_polar.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col() +
  coord_polar(theta = "y")

Basic pie chart in ggplot2

Color of the lines

The borders of the pie can be changed with the color argument of the geom_bar or geom_col function.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  coord_polar(theta = "y")

Pie chart border color

Text and labels

Pie chart with text in ggplot

Adding text

By default, the values are not displayed inside each slice. You can add them with geom_text. Note that position_stack(vjust = 0.5) will place the labels in the correct position.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y")

ggplot2 pie chart with labels

Adding labels

An alternative to geom_text is using geom_label, which adds a border around the values. If you set this the legend will display the letter “a” inside the boxes, so we have overridden this behavior with show.legend = FALSE.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_label(aes(label = value),
             position = position_stack(vjust = 0.5),
             show.legend = FALSE) +
  coord_polar(theta = "y")

Color of the labels of the pie

Labels color

Note that you can change the color of the labels with color.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_label(aes(label = value),
             color = "white",
             position = position_stack(vjust = 0.5),
             show.legend = FALSE) +
  coord_polar(theta = "y")

Color customization

Color palette

The default color palette can be changed with a predefined color palette, such as the scale_fill_brewer or scale_fill_viridis_d.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  scale_fill_brewer()

Pie chart color palette customization

Custom colors

If you prefer setting your own colors you can make use of scale_fill_manual and set the corresponding colors.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  scale_fill_manual(values = c("#BE2A3E", "#EC754A",
                               "#EACF65", "#3C8D53"))

Pie chart color selection

Theme customization

Change the theme of the pie chart

The default pie chart styling can be changed in ggplot2 making use of themes.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  scale_fill_brewer() +
  theme_bw()

Pie chart with void theme in ggplot2

You can also remove the whole theme with theme_void.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  scale_fill_brewer() +
  theme_void()

You can get a customized style customizing the theme components. Note that you can create your custom theme if you want to reproduce the styling.

Beautiful pie chart in ggplot2

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  scale_fill_brewer() +
  theme(axis.text = element_blank(),
        axis.ticks = element_blank(),
        axis.title = element_blank(),
        panel.grid = element_blank(),
        panel.background = element_rect(fill = "#ebf2ff"),
        plot.background = element_rect(fill = "#ebf2ff"),
        legend.background = element_rect(fill = "#ebf2ff"))

Legend customization

Legend title

The default legend title is the name of the categorical variable of the input data frame. Change it following the example below.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  guides(fill = guide_legend(title = "Title"))

Pie chart legend title in ggplot

Legend labels

The labels of the lagend can also be modified. Use the labels argument of scale_fill_discrete or scale_fill_manual.

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  scale_fill_discrete(labels = c("A", "B", "C", "D"))

Pie chart legend labels

Legend position

The legend can be placed in several positions with the legend.position component of the theme function. Possible placement values are "bottom", "left", "top" and "right" (default).

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  theme(legend.position = "bottom")

Legend position in ggplot2

Remove the legend

If you prefer removing the legend set the position component to "none".

# install.packages("ggplot2")
library(ggplot2)

ggplot(df, aes(x = "", y = value, fill = group)) +
  geom_col(color = "black") +
  geom_text(aes(label = value),
            position = position_stack(vjust = 0.5)) +
  coord_polar(theta = "y") +
  theme(legend.position = "none")

Remove the legend of a ggplot2 pie chart