Basic Pyramid Chart — ggplot2

A pyramid chart displays two opposing horizontal bar charts that share a central axis, creating a pyramid or butterfly shape. This visualization is ideal for comparing two related metrics across the same categories, revealing asymmetries and patterns in bidirectional data. Most commonly used for population pyramids showing age-gender distributions.

Basic Pyramid Chart rendered with ggplot2

Renders

R source (ggplot2)

#' anyplot.ai
#' pyramid-basic: Basic Pyramid Chart
#' Library: ggplot2 3.5.1 | R 4.4.1
#' Quality: 87/100 | Created: 2026-09-05

library(ggplot2)
library(dplyr)
library(tidyr)
library(scales)
library(ragg)

set.seed(42)

# --- Theme tokens -----------------------------------------------------------
THEME       <- Sys.getenv("ANYPLOT_THEME", "light")
PAGE_BG     <- if (THEME == "light") "#FAF8F1" else "#1A1A17"
ELEVATED_BG <- if (THEME == "light") "#FFFDF6" else "#242420"
INK         <- if (THEME == "light") "#1A1A17" else "#F0EFE8"
INK_SOFT    <- if (THEME == "light") "#4A4A44" else "#B8B7B0"

IMPRINT_MALE   <- "#4467A3"  # Imprint palette position 3 — blue (sky/male convention)
IMPRINT_FEMALE <- "#954477"  # Imprint palette position 7 — rose (wellness/female convention)

# --- Data --------------------------------------------------------------------
age_groups <- c(
  "0-9", "10-19", "20-29", "30-39", "40-49",
  "50-59", "60-69", "70-79", "80+"
)

df <- tibble::tibble(
  category    = factor(age_groups, levels = age_groups),
  value_left  = c(4.8, 5.1, 4.6, 4.2, 4.4, 4.0, 3.1, 1.9, 0.9),
  value_right = c(4.6, 4.9, 4.5, 4.3, 4.6, 4.3, 3.4, 2.3, 1.3)
) %>%
  mutate(value_left = -value_left)

plot_df <- df %>%
  pivot_longer(
    cols = c(value_left, value_right),
    names_to = "side",
    values_to = "population"
  ) %>%
  mutate(
    side = factor(side,
      levels = c("value_left", "value_right"),
      labels = c("Male", "Female")
    )
  )

axis_limit <- max(abs(df$value_left), df$value_right) * 1.15

# --- Plot ---------------------------------------------------------------------
p <- ggplot(plot_df, aes(x = category, y = population, fill = side)) +
  geom_col(width = 0.75) +
  geom_text(
    aes(
      label = sprintf("%.1f", abs(population)),
      hjust = ifelse(population < 0, 1.15, -0.15)
    ),
    size = 2.6, color = INK_SOFT, show.legend = FALSE
  ) +
  coord_flip() +
  scale_y_continuous(
    limits = c(-axis_limit, axis_limit),
    labels = function(x) label_number(accuracy = 1)(abs(x))
  ) +
  scale_fill_manual(values = c("Male" = IMPRINT_MALE, "Female" = IMPRINT_FEMALE)) +
  labs(
    title = "pyramid-basic · r · ggplot2 · anyplot.ai",
    x     = "Age Group",
    y     = "Population (millions)",
    fill  = NULL
  ) +
  theme_minimal(base_size = 8) +
  theme(
    plot.background    = element_rect(fill = PAGE_BG, color = PAGE_BG),
    panel.background   = element_rect(fill = PAGE_BG, color = NA),
    panel.grid.major.x = element_line(color = INK, linewidth = 0.3),
    panel.grid.major.y = element_blank(),
    panel.grid.minor   = element_blank(),
    axis.title         = element_text(color = INK, size = 10),
    axis.text          = element_text(color = INK_SOFT, size = 8),
    axis.line.x.bottom = element_line(color = INK_SOFT, linewidth = 0.3),
    axis.line.x.top    = element_blank(),
    axis.line.y.left   = element_line(color = INK_SOFT, linewidth = 0.3),
    axis.line.y.right  = element_blank(),
    plot.title         = element_text(color = INK, size = 12),
    legend.position     = "top",
    legend.background   = element_rect(fill = ELEVATED_BG, color = NA),
    legend.text         = element_text(color = INK_SOFT, size = 8),
    legend.title        = element_text(color = INK)
  )

# --- Save -----------------------------------------------------------------
ggsave(
  filename = sprintf("plot-%s.png", THEME),
  plot     = p,
  device   = ragg::agg_png,
  width    = 8,
  height   = 4.5,
  units    = "in",
  dpi      = 400
)

Retrieve this implementation

Runnable source as JSON, for any HTTP client: https://api.anyplot.ai/specs/pyramid-basic/ggplot2/code. Any spec id and library id listed in llms-full.txt fit the same URL shape; every URL below is complete and callable.

{
  "spec_id": "pyramid-basic",
  "language": "r",
  "library": "ggplot2",
  "page": "https://anyplot.ai/pyramid-basic/r/ggplot2",
  "hub": "https://anyplot.ai/pyramid-basic",
  "code_json": "https://api.anyplot.ai/specs/pyramid-basic/ggplot2/code",
  "spec_json": "https://api.anyplot.ai/specs/pyramid-basic",
  "render_light_png": "https://storage.googleapis.com/anyplot-images/plots/pyramid-basic/r/ggplot2/plot-light.png",
  "render_dark_png": "https://storage.googleapis.com/anyplot-images/plots/pyramid-basic/r/ggplot2/plot-dark.png",
  "quality_score": 87.0,
  "license": "MIT",
  "guide": "https://anyplot.ai/llms.txt"
}

Part of Basic Pyramid Chart on anyplot.ai.

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