Python f-string cheat sheets (2022)

Summary

Python f-string cheat sheets See fstring.help for more examples and for a more detailed discussion of this syntax see this string formatting article. All numbers The below examples assume the following variables: >>> number = 4125.6 >>> percent = 0.3738 Example Output Replacement Field Fill Width Grouping Precision Type '4125.60' {number:.2f} .2 f '4,125.60' {number:,.2f} , .2 f '04125.60' {number:08.2f} 0 8 .2 f ' 4125.60' {number: 8.2f} 8 .2 f '4.1e+03' {number:.2g} .2 g '4125.6' {number:.8g} .8 g '37%' {percent:.0%} .0 % These format specifications only work on all numbers (both int and float). Type f with precision .n displays n digits after the decimal point. Type g with precision .n displays n significant digits in scientific notation. Trailing zeros are not displayed. Integers These examples assume the following variable: >>> number = 10 Example Output Replacement Field Alt Fill Width Grouping Type '0010' {number:04d} 0 4 d ' 10' {number: 4d} 4 d '10' {number:,} , '1010' {number:b} b 'a' {number:x} x 'A' {number:X} X '0xa' {number:#x} # x '000a' {number:04x} 0 4 x '0000_1010' {number:09_b} 0 9 _ b An empty type is synonymous with d for integers. These format specifications only work on integers (int). Strings These examples assume the following variable: >>> string = "Python" Example Output Replacement Field Fill Char Align Width ' Python' {string:>20} > 20 'Python ' {string:<20} < 20 ' Python ' {string:^20} ^ 20 '0000Python' {string:0>10} 0 > 10 These format specifications work on strings (str) and most other types (any type that doesn't specify its own custom format specifications). All objects The below modifiers are special syntaxes supported by all object types. Some format specifications are also included to show how to mix and match these syntaxes with the : syntax. Self-Doc Conversion Format Spec Field Example Output !s {expression!s} 'Hi! ✨' !r {expression!r} "'Hi! ✨'" !a {expression!a} "'Hi! \\u2728'" !r <10 {expression!r:<10} "'Hi! ✨' " = {expressi...