Format Specifiers List

Most Commonly Used Format Specifiers:

Specifier	What it does	Most common modern usage example	Notes / Very common variants
%d or %i	Signed decimal integer	printf("Age: %d\n", age);	%d is slightly more common today
%s	Null-terminated string	printf("Name: %s\n", name);	By far the most used non-numeric specifier
%f	Floating-point (decimal notation)	printf("Pi ≈ %.2f\n", 3.14159);	Often used with precision: %.2f, %.3f
%c	Single character	printf("Initial: %c\n", ch);	Very frequent for single chars
%lld	Signed 64-bit integer (long long)	printf("Big number: %lld\n", fileSize);	Extremely common in 2025 (64-bit era)
%u	Unsigned decimal integer	printf("Count: %u\n", items);	Used when values are guaranteed non-negative
%zu	size_t (unsigned size type)	printf("Length: %zu\n", strlen(str));	Dominant choice for sizes, lengths, counts
%p	Pointer/address (usually hex)	printf("Ptr: %p\n", (void*)ptr);	Essential for debugging pointers

    printf("int:         %d\n",        n);          // 42
    printf("string:      %s\n",        name);       // Alice
    printf("float:       %.3f\n",      pi);         // 3.142
    printf("char:        %c\n",        initial);    // A
    printf("size_t:      %zu\n",       len);        // 5
    printf("long long:   %lld\n",      huge);       // 1234567890123
    printf("pointer:     %p\n",        ptr);        // (some hex address)
    printf("hex:         0x%X\n",      255);        // 0xFF
    printf("percent:     100%%\n");                 // 100%