diff --git a/docs/03.API-EXAMPLE.md b/docs/03.API-EXAMPLE.md
index 1ffe2e8d8..e5ca6da72 100644
--- a/docs/03.API-EXAMPLE.md
+++ b/docs/03.API-EXAMPLE.md
@@ -551,6 +551,50 @@ Value of x is 12
 Value of x is 17
 ```
 
+## Step 8. Changing the seed of pseudorandom generated numbers
+
+If you want to change the seed of `Math.random()` generated numbers, you have to initialize the seed value with `srand`.
+A recommended method is using `jerry_port_get_current_time()` or something based on a constantly changing value, therefore every run produces truly random numbers.
+
+[doctest]: # ()
+
+```c
+#include <string.h>
+#include <stdlib.h>
+#include "jerryscript.h"
+#include "jerryscript-port.h"
+#include "jerryscript-ext/handler.h"
+
+int
+main (void)
+{
+  /* Initialize srand value */
+  srand ((unsigned) jerry_port_get_current_time ());
+
+  /* Generate a random number, and print it */
+  const jerry_char_t script[] = "var a = Math.random (); print(a)";
+  size_t script_size = strlen ((const char *) script);
+
+  /* Initialize the engine */
+  jerry_init (JERRY_INIT_EMPTY);
+
+  /* Register the print function */
+  jerryx_handler_register_global ((const jerry_char_t *) "print",
+                                  jerryx_handler_print);
+
+  /* Evaluate the script */
+  jerry_value_t eval_ret = jerry_eval (script, script_size, false);
+
+  /* Free the JavaScript value returned by eval */
+  jerry_release_value (eval_ret);
+
+  /* Cleanup the engine */
+  jerry_cleanup ();
+
+  return 0;
+}
+```
+
 ## Further steps
 
 For further API description, please visit [API Reference page](https://jerryscript-project.github.io/jerryscript/api-reference/) on [JerryScript home page](https://jerryscript-project.github.io/jerryscript/).
diff --git a/jerry-main/main-unix-minimal.c b/jerry-main/main-unix-minimal.c
index 87bb05f6d..bb0438881 100644
--- a/jerry-main/main-unix-minimal.c
+++ b/jerry-main/main-unix-minimal.c
@@ -71,6 +71,7 @@ int
 main (int argc,
       char **argv)
 {
+  srand ((unsigned) jerry_port_get_current_time ());
   if (argc <= 1 || (argc == 2 && (!strcmp ("-h", argv[1]) || !strcmp ("--help", argv[1]))))
   {
     print_help (argv[0]);
diff --git a/jerry-main/main-unix.c b/jerry-main/main-unix.c
index e1590d007..0bfaacccc 100644
--- a/jerry-main/main-unix.c
+++ b/jerry-main/main-unix.c
@@ -424,6 +424,7 @@ int
 main (int argc,
       char **argv)
 {
+  srand ((unsigned) jerry_port_get_current_time ());
   const char *file_names[argc];
   int files_counter = 0;
 
diff --git a/targets/curie_bsp/jerry_app/quark/main.c b/targets/curie_bsp/jerry_app/quark/main.c
index e7b49a60f..d9984633d 100644
--- a/targets/curie_bsp/jerry_app/quark/main.c
+++ b/targets/curie_bsp/jerry_app/quark/main.c
@@ -136,6 +136,7 @@ void eval_jerry_script (int argc, char *argv[], struct tcmd_handler_ctx *ctx)
 
 void jerry_start ()
 {
+  srand ((unsigned) jerry_port_get_current_time ());
   jerry_init (JERRY_INIT_EMPTY);
   jerry_value_t global_obj_val = jerry_get_global_object ();
   jerry_value_t print_func_name_val = jerry_create_string ((jerry_char_t *) "print");
diff --git a/targets/mbed/source/main.cpp b/targets/mbed/source/main.cpp
index 39aedb1a3..21f0d0d47 100644
--- a/targets/mbed/source/main.cpp
+++ b/targets/mbed/source/main.cpp
@@ -24,6 +24,7 @@ static Serial pc (USBTX, USBRX); //tx, rx
 
 static int jerry_task_init (void)
 {
+  srand ((unsigned) jerry_port_get_current_time ());
   int retcode;
 
   DECLARE_JS_CODES;
diff --git a/targets/mbedos5/jerryscript-mbed/jerryscript-mbed-launcher/source/launcher.cpp b/targets/mbedos5/jerryscript-mbed/jerryscript-mbed-launcher/source/launcher.cpp
index edeca99a7..51b55b547 100644
--- a/targets/mbedos5/jerryscript-mbed/jerryscript-mbed-launcher/source/launcher.cpp
+++ b/targets/mbedos5/jerryscript-mbed/jerryscript-mbed-launcher/source/launcher.cpp
@@ -67,6 +67,7 @@ static int load_javascript() {
 }
 
 int jsmbed_js_init() {
+    srand ((unsigned) jerry_port_get_current_time());
     jerry_init_flag_t flags = JERRY_INIT_EMPTY;
     jerry_init(flags);
 
diff --git a/targets/riot-stm32f4/source/main-riotos.c b/targets/riot-stm32f4/source/main-riotos.c
index bb770723d..ddeb362d2 100644
--- a/targets/riot-stm32f4/source/main-riotos.c
+++ b/targets/riot-stm32f4/source/main-riotos.c
@@ -97,6 +97,7 @@ const shell_command_t shell_commands[] = {
 
 int main (void)
 {
+  srand ((unsigned) jerry_port_get_current_time ());
   printf ("You are running RIOT on a(n) %s board.\n", RIOT_BOARD);
   printf ("This board features a(n) %s MCU.\n", RIOT_MCU);
 
diff --git a/targets/zephyr/src/main-zephyr.c b/targets/zephyr/src/main-zephyr.c
index a109589c4..5be3782e4 100644
--- a/targets/zephyr/src/main-zephyr.c
+++ b/targets/zephyr/src/main-zephyr.c
@@ -79,6 +79,7 @@ static int shell_cmd_handler (char *source_buffer)
 
 void main (void)
 {
+  srand ((unsigned) jerry_port_get_current_time ());
   uint32_t zephyr_ver = sys_kernel_version_get ();
   printf ("JerryScript build: " __DATE__ " " __TIME__ "\n");
   printf ("JerryScript API %d.%d\n", JERRY_API_MAJOR_VERSION, JERRY_API_MINOR_VERSION);
diff --git a/tests/unit-core/test-common.h b/tests/unit-core/test-common.h
index e9f2cdab5..3a647d564 100644
--- a/tests/unit-core/test-common.h
+++ b/tests/unit-core/test-common.h
@@ -47,25 +47,7 @@
 #define TEST_INIT() \
 do \
 { \
-  FILE *f_rnd = fopen ("/dev/urandom", "r"); \
- \
-  if (f_rnd == NULL) \
-  { \
-    return 1; \
-  } \
- \
-  uint32_t seed; \
- \
-  size_t bytes_read = fread (&seed, 1, sizeof (seed), f_rnd); \
- \
- fclose (f_rnd); \
- \
-  if (bytes_read != sizeof (seed)) \
-  { \
-    return 1; \
-  } \
- \
-  srand (seed); \
+  srand ((unsigned) jerry_port_get_current_time ()); \
 } while (0)
 
 #endif /* !TEST_COMMON_H */