diff --git a/py/formatfloat.c b/py/formatfloat.c
index caecb0f..d1b12cd 100644
--- a/py/formatfloat.c
+++ b/py/formatfloat.c
@@ -75,7 +75,7 @@
 
     if (buf_size < 7) {
         // Smallest exp notion is -9e+99 which is 6 chars plus terminating
-        // nulll.
+        // null.
 
         if (buf_size >= 2) {
             *s++ = '?';