How to Convert Index to Column in Pandas (With Examples)


You can use the following basic syntax to convert an index of a pandas DataFrame to a column:

#convert index to column
df.reset_index(inplace=True)

If you have a MultiIndex pandas DataFrame, you can use the following syntax to convert a specific level of the index to a column:

#convert specific level of MultiIndex to column
df.reset_index(inplace=True, level = ['Level1'])

The following examples show how to use this syntax in practice.

Example 1: Convert Index to Column

The following code shows how to convert an index of a pandas DataFrame to a column:

import pandas as pd

#create DataFrame
df = pd.DataFrame({'points': [25, 12, 15, 14, 19],
                   'assists': [5, 7, 7, 9, 12],
                   'rebounds': [11, 8, 10, 6, 6]})

#view DataFrame
df

points	assists	rebounds
0	25	5	11
1	12	7	8
2	15	7	10
3	14	9	6
4	19	12	6

#convert index to column
df.reset_index(inplace=True)

#view updated DataFrame
df

	index	points	assists	rebounds
0	0	25	5	11
1	1	12	7	8
2	2	15	7	10
3	3	14	9	6
4	4	19	12	6

Example 2: Convert MultiIndex to Columns

Suppose we have the following MultiIndex pandas DataFrame:

import pandas as pd

#create DataFrame
index_names = pd.MultiIndex.from_tuples([('Level1','Lev1', 'L1'),
                                       ('Level2','Lev2', 'L2'),
                                       ('Level3','Lev3', 'L3'),
                                       ('Level4','Lev4', 'L4')],
                                       names=['Full','Partial', 'ID'])

data = {'Store': ['A','B','C','D'],
        'Sales': [17, 22, 29, 35]}

df = pd.DataFrame(data, columns = ['Store','Sales'], index=index_names)

#view DataFrame
df

                    Store    Sales
Full	Partial	ID		
Level1	Lev1	L1	A	17
Level2	Lev2	L2	B	22
Level3	Lev3	L3	C	29
Level4	Lev4	L4	D	35

The following code shows how to convert every level of the MultiIndex to columns in a pandas DataFrame:

#convert all levels of index to columns
df.reset_index(inplace=True)

#view updated DataFrame
df

        Full	Partial	ID	Store	Sales
0	Level1	Lev1	L1	A	17
1	Level2	Lev2	L2	B	22
2	Level3	Lev3	L3	C	29
3	Level4	Lev4	L4	D	35

We could also use the following code to only convert a specific level of the MultiIndex to a column:

#convert just 'ID' index to column in DataFrame
df.reset_index(inplace=True, level = ['ID'])

#view updated DataFrame
df

		ID	Store	Sales
Full	Partial			
Level1	Lev1	L1	A	17
Level2	Lev2	L2	B	22
Level3	Lev3	L3	C	29
Level4	Lev4	L4	D	35

Notice that just the ‘ID’ level was converted to a column in the DataFrame.

Additional Resources

The following tutorials explain how to perform other common functions in pandas:

How to Set Column as Index in Pandas
How to Drop Columns by Index in Pandas
How to Sort DataFrame by Both Index and Column in Pandas

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