What is printf formatting?

Printf (print formatted) is a C function that formats output using format specifiers like %s (string), %d (integer), %f (float), and %x (hex). The same pattern is used in Python's % operator, C's sprintf, and many other languages.

%05d formats an integer with zero-padding to a minimum width of 5 digits. For example, printf('%05d', 42) outputs '00042'.

Printf Formatter — Format Strings with C-style Specifiers

Printf-style formatting is a fundamental string operation used across C, C++, Python (% operator and old-style formatting), Java (String.format), PHP, Ruby, and many other languages. Understanding format specifiers lets you control precisely how numbers, strings, and other values are displayed.

Printf Specifier Reference

%s — string
%d or %i — signed decimal integer
%f — decimal floating point (default 6 decimal places)
%.2f — float with exactly 2 decimal places
%e — scientific notation (e.g., 1.23e+04)
%x — lowercase hexadecimal integer
%X — uppercase hexadecimal integer
%o — octal integer
%% — literal percent sign

Frequently Asked Questions

What does %0.2f mean?

%.2f formats a floating-point number with exactly 2 decimal places. The 0 flag (as in %05.2f) adds zero-padding to reach the specified minimum width. Example: printf('%05.2f', 3.1) → '03.10'.

Does this work with Python format strings?

This tool implements the classic C-style % formatting that is also used in Python's old-style string formatting (e.g. 'Hello %s' % 'World'). Python's newer f-strings and str.format() use different syntax.

Printf Formatter online

Format strings with C/Python printf-style specifiers (%s, %d, %f, %x) — runs in your browser

Printf Specifier Reference

Frequently Asked Questions

What does %0.2f mean?

Does this work with Python format strings?