Python | Add leading zeros to string

Michael Zippo 18.07.2021

👻 Check our latest review to choose the best laptop for Machine Learning engineers and Deep learning tasks!

Method # 1: Using rjust()

The rjust function offers a one-line a way to accomplish this specific task. Hence, it can be easily used for any line that we need to fill. We can specify the required amount of padding.

# Python3 demo code
# adding leading zeros
# using rjust ()

# initialization string

test_string = ’GFG’

# print the original string

print ( "The original string:" + str (test_string))

# of zeros required < / p>

N = 4

# using rjust ()
# adding leading zero

res = test_string.rjust (N + len (test_string), ’0’ )

# print result

print ( "The string after adding leading zeros:" + str (res))

Output:

 The original string: GFG The string after adding leading zeros: 0000GFG

Method # 2: Using zfill()

This is another way to accomplish this specific task, in this function we do not need to specify the letter that we need to complete, this function is solely for filling zeros inside and therefore is recommended.

# Python3 code for demonstration
# adding leading zeros
# using zfill ()

# initialization string

test_string = ’GFG’

# print the original line

print ( "The original string:" + str (test_string))

# Of zeros required

N = 4

# using zfill ()
# add leading zero

res = test_string.zfill (N + len (test_string))

# print result

print ( "The string after adding leading zeros:" + str (res))

Output:

 The original string: GFG The string after adding leading zeros: 0000GFG

👻 Read also: what is the best laptop for engineering students?

We hope this article has helped you to resolve the problem. Apart from Python | Add leading zeros to string, check other code Python module-related topics.

Want to excel in Python? See our review of the best Python online courses 2023. If you are interested in Data Science, check also how to learn programming in R.

By the way, this material is also available in other languages: