diff --git a/cores/esp8266/WMath.cpp b/cores/esp8266/WMath.cpp
index d9d87da5a..1f0c8d7db 100644
--- a/cores/esp8266/WMath.cpp
+++ b/cores/esp8266/WMath.cpp
@@ -70,11 +70,11 @@ long secureRandom(long howsmall, long howbig) {
 }
 
 long map(long x, long in_min, long in_max, long out_min, long out_max) {
-    long divisor = (in_max - in_min) + out_min;
+    long divisor = (in_max - in_min);
     if(divisor == 0){
         return -1; //AVR returns -1, SAM returns 0
     }
-    return (x - in_min) * (out_max - out_min) / divisor;
+    return (x - in_min) * (out_max - out_min) / divisor + out_min;
 }
 
 unsigned int makeWord(unsigned int w) {