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Python: What is an f-string?

adamlombard profile image Adam Lombard (he/him) Updated on ・1 min read

In Python, f-strings are a string formatting mechanism that allow us to embed Python expressions in string literals. 'F-string' is short for 'formatted string'.

They are formatted like so:

f"string literal {expression}"
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Say, for instance, we want to print a user greeting where the username is variable:

username = 'Ellen'
print(f"Hello, {username}!")
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Hello, Ellen!
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Any valid Python expression can be used in the f-string brackets:

year = 2020
print(f"The year is {year}. A decade from now, the year will be {year + 10}.")
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The year is 2020. A decade from now, the year will be 2030.
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F-strings were added in Python 3.6.

Discussion (12)

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waylonwalker profile image
Waylon Walker

Any version of python before 3.6 was dead to me the instant f-strings came out. They are so freaking useful!

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adamlombard profile image
Adam Lombard (he/him) Author

Yes, they're very handy!

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muhimen123 profile image
Muhimen

f-string? Better way to use .format()

Keep in mind, f-string is only available for python 3.6 and upper

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adrianmarkperea profile image
Adrian Perea

I find the syntax of format a little bit harder to read than f-strings. F-strings make strings with variables read like prose

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adamlombard profile image
Adam Lombard (he/him) Author

Thank you for noting the Python version. Excellent point!

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syntax753 profile image
Peter Turner • Edited

Shouldn't you edit the article to mention the version?
Good article in any case :)

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adamlombard profile image
Adam Lombard (he/him) Author

Yes, thanks for the suggestion. :)

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sanyaldips93 profile image
Dipayan Sanyal

A nice shorthand of the format function.

A beautiful explanation. (Y)

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muhimen123 profile image
Muhimen

What is that (Y) doing at the end? 😅

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sanyaldips93 profile image
Dipayan Sanyal

I was trying to give a thumbs up

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eljayadobe profile image
Eljay-Adobe

(👍🏻)

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adamlombard profile image
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