lubridate (version 1.7.10)

as_date: Convert an object to a date or date-time


Convert an object to a date or date-time


as_date(x, ...)

# S4 method for ANY as_date(x, ...)

# S4 method for POSIXt as_date(x, tz = NULL)

# S4 method for numeric as_date(x, origin = lubridate::origin)

# S4 method for character as_date(x, tz = NULL, format = NULL)

as_datetime(x, ...)

# S4 method for POSIXt as_datetime(x, tz = "UTC")

# S4 method for numeric as_datetime(x, origin = lubridate::origin, tz = "UTC")

# S4 method for character as_datetime(x, tz = "UTC", format = NULL)

# S4 method for ANY as_datetime(x, tz = "UTC")



a vector of POSIXt, numeric or character objects


further arguments to be passed to specific methods (see above).


a time zone name (default: time zone of the POSIXt object x). See OlsonNames().


a Date object, or something which can be coerced by as.Date(origin, ...) to such an object (default: the Unix epoch of "1970-01-01"). Note that in this instance, x is assumed to reflect the number of days since origin at "UTC".


format argument for character methods. When supplied parsing is performed by strptime(). For this reason consider using specialized parsing functions in lubridate.


a vector of Date objects corresponding to x.

Compare to base R

These are drop in replacements for as.Date() and as.POSIXct(), with a few tweaks to make them work more intuitively.

  • Called on a POSIXct object, as_date() uses the tzone attribute of the object to return the same date as indicated by the printed representation of the object. This differs from as.Date, which ignores the attribute and uses only the tz argument to as.Date() ("UTC" by default).

  • Both functions provide a default origin argument for numeric vectors.

  • Both functions will generate NAs for invalid date format. A warning message will provide a count of the elements that were not converted

  • as_datetime() defaults to using UTC.


dt_utc <- ymd_hms("2010-08-03 00:50:50")
dt_europe <- ymd_hms("2010-08-03 00:50:50", tz="Europe/London")
c(as_date(dt_utc), as.Date(dt_utc))
c(as_date(dt_europe), as.Date(dt_europe))
## need not supply origin
## Will replace invalid date format with NA
dt_wrong <- c("2009-09-29", "2012-11-29", "2015-29-12")
# }