Very basic C code that benchmarks both the 'stdio' and the 'printf' function. WARNING: This is an extremely simple benchmark. The results heavily depend on your 'terminal', 'stdio' and 'printf' implementation.

printf_benchmark.c

/*
 * Author: Tuna Cici
 * Date: 30 May 2023
 *
 * This file contains the benchmarking code for the 'printf' function.
 * It is used to measure the time it takes to print a string to the 'stdout'.
 *
 */

#if defined(_WIN32) || defined(_WIN64)
#define OS_Windows
#elif defined(__linux__)
#define OS_Linux
#elif defined(__APPLE__)
#define OS_MacOS
#endif

/* Standard Libraries (printf & uint32_t) */
#include <stdio.h>
#include <stdint.h>

/* Time Library (timer with 'ms' resolution) */
#ifdef OS_Windows
#include <Windows.h>
#include <sysinfoapi.h>
#elif defined(OS_Linux) || defined(OS_MacOS)
#include <time.h>
#endif

void get_current_time(uint32_t *time)
{
#ifdef OS_Windows
    *time = GetTickCount();
#elif defined(OS_Linux) || defined(OS_MacOS)
    struct timespec ts;
    clock_gettime(CLOCK_MONOTONIC, &ts);
    *time = ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
#endif
}

void print_str(const char *str, uint32_t times)
{
    for (uint32_t i = 0u; i < times; i++)
    {
        printf("%s", str);
    }
}

int main(int argc, char const *argv[])
{
    const uint32_t CASE_1_SIZE = 1000u;
    const uint32_t CASE_2_SIZE = 10000u;
    const uint32_t CASE_3_SIZE = 100000u;

    const char STR_32[32] = "abcdefghijklmnopqrstuvwxyz12345";
    const char STR_64[64] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890_";
    const char STR_128[128] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890__";
    const char STR_256[256] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890__abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890___";

    uint32_t str_32_case1_start = 0u, str_32_case1_end = 0u;
    uint32_t str_32_case2_start = 0u, str_32_case2_end = 0u;
    uint32_t str_32_case3_start = 0u, str_32_case3_end = 0u;

    uint32_t str_64_case1_start = 0u, str_64_case1_end = 0u;
    uint32_t str_64_case2_start = 0u, str_64_case2_end = 0u;
    uint32_t str_64_case3_start = 0u, str_64_case3_end = 0u;

    uint32_t str_128_case1_start = 0u, str_128_case1_end = 0u;
    uint32_t str_128_case2_start = 0u, str_128_case2_end = 0u;
    uint32_t str_128_case3_start = 0u, str_128_case3_end = 0u;

    uint32_t str_256_case1_start = 0u, str_256_case1_end = 0u;
    uint32_t str_256_case2_start = 0u, str_256_case2_end = 0u;
    uint32_t str_256_case3_start = 0u, str_256_case3_end = 0u;

    /* BEGIN STR_32 */
    get_current_time(&str_32_case1_start);
    print_str(STR_32, CASE_1_SIZE);
    get_current_time(&str_32_case1_end);

    get_current_time(&str_32_case2_start);
    print_str(STR_32, CASE_2_SIZE);
    get_current_time(&str_32_case2_end);

    get_current_time(&str_32_case3_start);
    print_str(STR_32, CASE_3_SIZE);
    get_current_time(&str_32_case3_end);
    /* END STR_32 */

    /* BEGIN STR_64 */
    get_current_time(&str_64_case1_start);
    print_str(STR_64, CASE_1_SIZE);
    get_current_time(&str_64_case1_end);

    get_current_time(&str_64_case2_start);
    print_str(STR_64, CASE_2_SIZE);
    get_current_time(&str_64_case2_end);

    get_current_time(&str_64_case3_start);
    print_str(STR_64, CASE_3_SIZE);
    get_current_time(&str_64_case3_end);
    /* END STR_64 */

    /* BEGIN STR_128 */
    get_current_time(&str_128_case1_start);
    print_str(STR_128, CASE_1_SIZE);
    get_current_time(&str_128_case1_end);

    get_current_time(&str_128_case2_start);
    print_str(STR_128, CASE_2_SIZE);
    get_current_time(&str_128_case2_end);

    get_current_time(&str_128_case3_start);
    print_str(STR_128, CASE_3_SIZE);
    get_current_time(&str_128_case3_end);
    /* END STR_128 */

    /* BEGIN STR_256 */
    get_current_time(&str_256_case1_start);
    print_str(STR_256, CASE_1_SIZE);
    get_current_time(&str_256_case1_end);

    get_current_time(&str_256_case2_start);
    print_str(STR_256, CASE_2_SIZE);
    get_current_time(&str_256_case2_end);

    get_current_time(&str_256_case3_start);
    print_str(STR_256, CASE_3_SIZE);
    get_current_time(&str_256_case3_end);
    /* END STR_256 */

    printf("\n\n");

    printf("Case 1: Print %u times\n", CASE_1_SIZE);
    printf("\tSize 32: %u ms | Size 64: %u ms | Size 128: %u ms | Size 256: %u ms\n",
           str_32_case1_end - str_32_case1_start,
           str_64_case1_end - str_64_case1_start,
           str_128_case1_end - str_128_case1_start,
           str_256_case1_end - str_256_case1_start);

    printf("Case 2: Print %u times\n", CASE_2_SIZE);
    printf("\tSize 32: %u ms | Size 64: %u ms | Size 128: %u ms | Size 256: %u ms\n",
           str_32_case2_end - str_32_case2_start,
           str_64_case2_end - str_64_case2_start,
           str_128_case2_end - str_128_case2_start,
           str_256_case2_end - str_256_case2_start);

    printf("Case 3: Print %u times\n", CASE_3_SIZE);
    printf("\tSize 32: %u ms | Size 64: %u ms | Size 128: %u ms | Size 256: %u ms\n",
           str_32_case3_end - str_32_case3_start,
           str_64_case3_end - str_64_case3_start,
           str_128_case3_end - str_128_case3_start,
           str_256_case3_end - str_256_case3_start);

    return 0;
}

Simply compile with your choice of CC: clang -Wall printf_benchmark.c -o benchmark and run ./benchmark