How to Rename Columns in Pandas

Pandas has two ways to rename their Dataframe columns:

• first using the df.rename() function and
• second by using df.columns, which is the list representation of all the columns in dataframe.

Let’s Start with creating a dataframe and then we will see different ways to rename the columns of this dataframe and eventually how to reorder the column labels.

Create Dataframe

Let’s create a dataframe of Students details and each of the column has a special character $ prefixed to it’s columns name and we want to strip that special character from the column names

df = pd.DataFrame({'$name':['Allan','Mike','Brenda','Holy'], '$Age': [30,20,25,18],'$Zodiac':['Aries','Leo','Virgo','Libra'],'$Grade':['A','AB','B','AA'],'$City':['Aura','Somerville','Boon','Gannon']})

	$Name	$Age	$Zodiac	$Grade	$City
0	Allan	30	Aries	A	Aura
1	Mike	20	Leo	AB	Somerville
2	Brenda	25	Virgo	B	Boon
3	Holy	18	Libra	AA	Gannon

Pandas Rename Multiple Columns

pandas df.rename() api is used to alter the axes labels, It takes a dict-like or function transformations to apply to that axis’ values

Let’s rename all the column by stripping the character $ from it’s label, First we will create a dictionary of old and new column labels as shown below

The existing labels are the keys and the new column labels are the values in the dictionary.

column_labels = {'$Name': 'Name',
                '$Age': 'Age',
                '$Zodiac': 'Zodiac',
                '$Grade': 'Grade',
                '$City': 'City'}    

Next we will pass this dictionary to df.rename() to rename the column labels of the dataframe

df.rename(columns=column_labels,inplace=True)

Alternatively, we can also replace the $ character for all the column labels using the df.columns as shown below

df.columns=[it.replace('$','') for it in df.columns]
df

	Name	Age	Zodiac	Grade	City
0	Allan	30	Aries	A	Aura
1	Mike	20	Leo	AB	Somerville
2	Brenda	25	Virgo	B	Boon
3	Holy	18	Libra	AA	Gannon

Pandas set column names

We will replace the df.columns list value with the new list values which is created by stripping the $ character from the column labels

Let’s create this new list using the str.replace() function and after that assign this new list to df.columns

df.columns = df.columns.str.replace('$','')

Let’s check the new column labels in df.columns list

df.columns
Out: Index(['Age', 'City', 'Grade', 'Zodiac', 'name'], dtype='object')

The new column values doesn’t have those $ character in the column name

	Name	Age	Zodiac	Grade	City
0	Allan	30	Aries	A	Aura
1	Mike	20	Leo	AB	Somerville
2	Brenda	25	Virgo	B	Boon
3	Holy	18	Libra	AA	Gannon

Pandas rename column with a list

We can replace the existing column labels with the new column labels in the list by assigning the value to df.columns as shown below

Here we changed the column labels to it’s german equivalent

df.columns = ['Nennen','Das Alter','Tierkreis','Klasse','Stadt']
df

	Nennen	Das Alter	Tierkreis	Klasse	Stadt
0	Allan	30	Aries	A	Aura
1	Mike	20	Leo	AB	Somerville
2	Brenda	25	Virgo	B	Boon
3	Holy	18	Libra	AA	Gannon

Pandas Rename Columns by Index

We can rename the columns by their Index as well, we will first create a dictionary as shown below, where the keys of dictionary will be selected by the index of the column

Here we want to rename the first and third column in the dataframe to col1 & col3 respectively

column_labels_index = {
                df.columns[0]: 'Col1',
                df.columns[2]: 'Col3'
                }  

Next we will pass the above dictionary to df.rename() function

df.rename(columns=column_labels_index, inplace=True)

	Col1	Age	Col3	Grade	City
0	Allan	30	Aries	A	Aura
1	Mike	20	Leo	AB	Somerville
2	Brenda	25	Virgo	B	Boon
3	Holy	18	Libra	AA	Gannon

Reorder Columns in Pandas using df.columns

We want to re-order the column by moving the Name column to the last and Age column to the first.

Let’s see how we can do this by simply assigning the new values in a list to df.columns

# Re-order Columns
df.columns = ['Age','Zodiac','Grade','City','Name']
df

	Age	Zodiac	Grade	City	Name
0	30	Aries	A	Aura	Allan
1	20	Leo	AB	Somerville	Mike
2	25	Virgo	B	Boon	Brenda
3	18	Libra	AA	Gannon	Holy