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How to format a date in R

· 1 min read · Updated March 15, 2026 · beginner
r dates lubridate formatting

Formatting dates is essential for reporting and data visualization. Here are several approaches.

With base R

Use format() with strptime codes:

# Create a date
date_obj <- as.Date("2026-03-15")

# Format as Year-Month-Day
format(date_obj, "%Y-%m-%d")
# [1] "2026-03-15"

# Format as Month Day, Year
format(date_obj, "%B %d, %Y")
# [1] "March 15, 2026"

# Short format
format(date_obj, "%m/%d/%y")
# [1] "03/15/26"

Common format codes:

  • %Y — 4-digit year
  • %y — 2-digit year
  • %m — month as number
  • %B — full month name
  • %b — abbreviated month
  • %d — day of month

With lubridate

The lubridate package makes this intuitive:

library(lubridate)

date_obj <- ymd("2026-03-15")

# Easy formatting
stamp("March 15, 2026")(date_obj)
# [1] "March 15, 2026"

# Extract parts
year(date_obj)
# [1] 2026
month(date_obj, label = TRUE)
# [1] Mar
day(date_obj)
# [1] 15

Common formats

x <- Sys.Date()

# ISO 8601
format(x, "%Y-%m-%d")

# US style
format(x, "%m/%d/%Y")

# European style
format(x, "%d/%m/%Y")

# With time
format(Sys.time(), "%Y-%m-%d %H:%M:%S")

See Also