gt Tables Exercises in R: 15 Practice Problems

Fifteen practice problems on gt tables: formatting numbers, headers, footnotes, colors, summary rows. Hidden solutions.

By Selva Prabhakaran · Published May 11, 2026 · Last updated May 11, 2026

RRun this once before any exercise

library(gt) library(dplyr) library(scales)

Exercise 1: Basic gt

Difficulty: Beginner.

Show solution

RInteractive R

head(mtcars, 5) |> gt()

Exercise 2: Title and subtitle

Difficulty: Beginner.

Show solution

RInteractive R

head(mtcars, 5) |> gt() |> tab_header(title = "Cars", subtitle = "Top 5")

Exercise 3: Format numeric column

Difficulty: Intermediate.

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RInteractive R

head(mtcars, 5) |> gt() |> fmt_number(mpg, decimals = 1)

Exercise 4: Format as currency

Difficulty: Intermediate.

Show solution

RInteractive R

diamonds |> head(5) |> gt() |> fmt_currency(price)

Exercise 5: Format percent

Difficulty: Intermediate.

Show solution

RInteractive R

tibble(rate = c(0.05, 0.10, 0.25)) |> gt() |> fmt_percent(rate)

Exercise 6: Color cells by value

Difficulty: Advanced.

Show solution

RInteractive R

head(mtcars, 5) |> gt() |> data_color(columns = mpg, colors = scales::col_numeric("Blues", domain = NULL))

Exercise 7: Footnote

Difficulty: Intermediate.

Show solution

RInteractive R

head(mtcars, 3) |> gt() |> tab_footnote(footnote = "Source: mtcars", locations = cells_title("title"))

Exercise 8: Column groups (spanners)

Difficulty: Advanced.

Show solution

RInteractive R

head(mtcars, 3) |> gt() |> tab_spanner(label = "Engine", columns = c(cyl, disp, hp))

Exercise 9: Hide a column

Difficulty: Intermediate.

Show solution

RInteractive R

head(mtcars, 3) |> gt() |> cols_hide(carb)

Exercise 10: Rename columns

Difficulty: Beginner.

Show solution

RInteractive R

head(mtcars, 3) |> gt() |> cols_label(mpg = "MPG", cyl = "Cyl")

Exercise 11: Summary row (grouped)

Difficulty: Advanced.

Show solution

RInteractive R

mtcars |> head(10) |> group_by(cyl) |> gt() |> summary_rows(groups = TRUE, columns = mpg, fns = list(mean = ~ mean(.x)))

Exercise 12: Add row groups

Difficulty: Advanced.

Show solution

RInteractive R

mtcars |> head(10) |> mutate(grp = ifelse(mpg > 20, "Hi","Lo")) |> gt(rowname_col = NULL, groupname_col = "grp")

Exercise 13: tab_style bold

Difficulty: Advanced.

Show solution

RInteractive R

head(mtcars, 5) |> gt() |> tab_style(style = cell_text(weight = "bold"), locations = cells_body(columns = mpg, rows = mpg > 25))

Exercise 14: Save to HTML/PNG

Difficulty: Intermediate.

Show solution

RInteractive R

g <- head(mtcars, 5) |> gt() gtsave(g, "out.html")

Exercise 15: Compact theme

Difficulty: Intermediate.

Show solution

RInteractive R

head(mtcars, 5) |> gt() |> opt_table_lines("none")

What to do next

Data-Visualization-Exercises (shipped), broader viz.
R-Markdown-Exercises (shipped), tables in reports.