Formatting dates in polars

dt.strftime

The representation of dates in data varies from region to region. In the USA, for instance, dates begin with the month rather than the day. Polars allows you to change how your dates are displayed depending on your audience. Below is a dataframe showing date values.

shape: (2, 1)

Num_Date
date
2025-09-17
2025-12-23

Format the date

You can format dates in either short or long form using the datetime component dt.strftime like this:

(df
 .with_columns(Short_Text_Date=pl.col('Num_Date').dt.strftime('%d %b, %Y'),
               Long_Text_Date=pl.col('Num_Date').dt.strftime('%d %B, %Y'),)
 )

shape: (2, 3)

Num_Date	Short_Text_Date	Long_Text_Date
date	str	str
2025-09-17	"17 Sep, 2025"	"17 September, 2025"
2025-12-23	"23 Dec, 2025"	"23 December, 2025"

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