{"id":21875,"date":"2022-04-04T18:49:05","date_gmt":"2022-04-04T13:19:05","guid":{"rendered":"http:\/\/www.pythonpool.com\/?p=21875"},"modified":"2026-07-13T12:39:41","modified_gmt":"2026-07-13T07:09:41","slug":"python-d","status":"publish","type":"post","link":"https:\/\/www.pythonpool.com\/python-d\/","title":{"rendered":"Python %d Formatting: Integer Placeholders and Modern Alternatives"},"content":{"rendered":"

Quick answer:<\/strong> %d is an old-style Python string-formatting placeholder for decimal integers. It is still useful when maintaining legacy printf-style formatting, but f-strings are usually clearer for new code. Check the value type, argument shape, width, padding, and percent escaping when debugging a formatting error. Remember that the result is a string, so formatting belongs at the presentation boundary rather than inside arithmetic or data-validation logic. Keeping the numeric value numeric until output also makes rounding and localization decisions easier to test.<\/p>\n

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%d is an old-style decimal integer placeholder; understand its type and width rules when maintaining older Python code, then prefer f-strings for new code.<\/figcaption><\/figure>\n

%d<\/code> in Python<\/strong> is an old-style string formatting placeholder for decimal integers. It is used with the %<\/code> operator, usually in older Python code:<\/p>\n

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age = 32\nprint(\"Age: %d\" % age)<\/code><\/pre>\n<\/div>\n
For new code, f-strings are usually clearer. Still, %d<\/code> is part of Python 3’s documented printf-style string formatting, so you will still see it in existing projects.<\/p>\n
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