diff --git a/src/libckpool.c b/src/libckpool.c
index 21f77753..633e072a 100644
--- a/src/libckpool.c
+++ b/src/libckpool.c
@@ -2168,8 +2168,8 @@ double diff_from_nbits(char *nbits)
 
 	pow = nbits[0];
 	powdiff = (8 * (0x1d - 3)) - (8 * (pow - 3));
-	if (powdiff < 8) // testnet only
-		powdiff = 8;
+	if (powdiff < 0) // testnet only
+		powdiff = 0;
 	diff32 = be32toh(*((uint32_t *)nbits)) & 0x00FFFFFF;
 	numerator = 0xFFFFULL << powdiff;