diff --git a/src/aio/aio.c b/src/aio/aio.c
index 92aa9f4..5335b5e 100644
--- a/src/aio/aio.c
+++ b/src/aio/aio.c
@@ -107,7 +107,7 @@ mraa_aio_init(unsigned int aio)
         syslog(LOG_ERR, "aio: pin %i beyond platform definition", pin);
         return NULL;
     }
-    if (aio > board->aio_count) {
+    if (aio >= board->aio_count) {
         syslog(LOG_ERR, "aio: requested channel out of range");
         return NULL;
     }
diff --git a/src/gpio/gpio.c b/src/gpio/gpio.c
index 8ae30fc..163cf79 100644
--- a/src/gpio/gpio.c
+++ b/src/gpio/gpio.c
@@ -145,7 +145,7 @@ mraa_gpio_init(int pin)
         pin = mraa_get_sub_platform_index(pin);
     }
 
-    if (pin < 0 || pin > board->phy_pin_count) {
+    if (pin < 0 || pin >= board->phy_pin_count) {
         syslog(LOG_ERR, "gpio: pin %i beyond platform definition", pin);
         return NULL;
     }