How to change column names of a data frame in R?

If you have a data frame df and want to rename all columns, you can do:

names(df) <- c("new_name1", "new_name2", "new_name3")

Ensure you have exactly as many new names as there are columns in df.

Using colnames()
colnames() is functionally similar to names() for data frames. For instance:

colnames(df) <- c("colA", "colB", "colC")

Either approach gives the same result.

Using dplyr::rename()
If you only need to rename some columns or prefer a pipe-friendly syntax:

library(dplyr)

df <- df %>%
  rename(
    new_col_name1 = old_col_name1,
    new_col_name2 = old_col_name2
  )

rename() maps new_name = old_name. You don’t need to rename every column at once; only specify those that need changes.

Pro Tips

Validate you’re not introducing duplicate names.
Always check your data after renaming to avoid referencing old column names in subsequent code.

Further Skill-Building
If you’d like to polish your data manipulation and interview problem-solving skills, consider:

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